for Journals by Title or ISSN
for Articles by Keywords
help
  Subjects -> PHYSICS (Total: 734 journals)
    - ELECTRICITY AND MAGNETISM (7 journals)
    - MECHANICS (18 journals)
    - NUCLEAR PHYSICS (44 journals)
    - OPTICS (84 journals)
    - PHYSICS (536 journals)
    - SOUND (17 journals)
    - THERMODYNAMICS (28 journals)

PHYSICS (536 journals)            First | 1 2 3 4 5 6 | Last

physica status solidi (b)     Hybrid Journal   (Followers: 1)
physica status solidi (c)     Hybrid Journal   (Followers: 1)
Physica Status Solidi - Rapid Research Letters     Hybrid Journal  
Physical Communication     Hybrid Journal  
Physical Review C     Full-text available via subscription   (Followers: 16)
Physical Review Special Topics - Physics Education Research     Open Access   (Followers: 5)
Physical Review X     Open Access   (Followers: 5)
Physical Sciences Data     Full-text available via subscription   (Followers: 1)
Physics - spotlighting exceptional research     Full-text available via subscription   (Followers: 1)
Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B     Full-text available via subscription   (Followers: 2)
Physics and Chemistry of Liquids: An International Journal     Hybrid Journal  
Physics and Chemistry of the Earth, Parts A/B/C     Hybrid Journal   (Followers: 3)
Physics in Medicine & Biology     Full-text available via subscription   (Followers: 7)
Physics in Perspective     Hybrid Journal   (Followers: 1)
Physics International     Open Access   (Followers: 2)
Physics Letters A     Hybrid Journal   (Followers: 9)
Physics Letters B     Open Access   (Followers: 2)
Physics of Fluids     Hybrid Journal   (Followers: 21)
Physics of Life Reviews     Hybrid Journal   (Followers: 1)
Physics of Plasmas     Hybrid Journal   (Followers: 6)
Physics of the Dark Universe     Open Access  
Physics of the Solid State     Hybrid Journal   (Followers: 3)
Physics of Wave Phenomena     Hybrid Journal   (Followers: 1)
Physics Procedia     Partially Free   (Followers: 1)
Physics Reports     Full-text available via subscription   (Followers: 1)
Physics Research International     Open Access   (Followers: 1)
Physics Today     Hybrid Journal   (Followers: 15)
Physics World     Full-text available via subscription   (Followers: 3)
Physics-Uspekhi     Full-text available via subscription  
Physik in unserer Zeit     Hybrid Journal  
Physik Journal     Hybrid Journal  
Plasma Physics and Controlled Fusion     Hybrid Journal   (Followers: 2)
Plasma Physics Reports     Hybrid Journal   (Followers: 2)
Pramana     Open Access   (Followers: 8)
Preview     Hybrid Journal  
Proceedings of the National Academy of Sciences     Full-text available via subscription   (Followers: 375)
Proceedings of the National Academy of Sciences, India Section A     Hybrid Journal   (Followers: 3)
Progress in Materials Science     Hybrid Journal   (Followers: 18)
Progress in Planning     Hybrid Journal   (Followers: 1)
Progress of Theoretical and Experimental Physics     Open Access  
Quantum Electronics     Full-text available via subscription   (Followers: 2)
Quantum Measurements and Quantum Metrology     Open Access  
Quarterly Journal of Mechanics and Applied Mathematics     Hybrid Journal   (Followers: 3)
Radiation Effects and Defects in Solids     Hybrid Journal   (Followers: 1)
Radiation Measurements     Hybrid Journal   (Followers: 2)
Radiation Physics and Chemistry     Hybrid Journal   (Followers: 1)
Radiation Protection Dosimetry     Hybrid Journal   (Followers: 1)
Radiation Research     Full-text available via subscription   (Followers: 2)
Radio Science     Full-text available via subscription   (Followers: 2)
Radiological Physics and Technology     Hybrid Journal   (Followers: 1)
Reflets de la physique     Full-text available via subscription  
Reports on Mathematical Physics     Full-text available via subscription  
Reports on Progress in Physics     Full-text available via subscription   (Followers: 2)
Research & Reviews : Journal of Physics     Full-text available via subscription  
Research in Drama Education     Hybrid Journal   (Followers: 8)
Research Journal of Physics     Open Access  
Results in Physics     Open Access   (Followers: 1)
Reviews in Mathematical Physics     Hybrid Journal  
Reviews of Accelerator Science and Technology     Hybrid Journal  
Reviews of Geophysics     Full-text available via subscription   (Followers: 17)
Reviews of Modern Physics     Full-text available via subscription   (Followers: 16)
Revista Colombiana de Física     Open Access  
Revista Mexicana de Astronomía y Astrofísica     Open Access  
Revista Mexicana de Física     Open Access  
Revista mexicana de física E     Open Access  
Rheologica Acta     Hybrid Journal   (Followers: 3)
Russian Journal of Mathematical Physics     Hybrid Journal  
Russian Journal of Nondestructive Testing     Hybrid Journal  
Russian Physics Journal     Hybrid Journal  
Samuel Beckett Today/Aujourd'hui     Full-text available via subscription   (Followers: 2)
Science and Technology of Nuclear Installations     Open Access   (Followers: 2)
Science China Physics, Mechanics and Astronomy     Hybrid Journal   (Followers: 1)
Science Foundation in China     Full-text available via subscription   (Followers: 2)
Scientific Journal of Physical Science     Open Access  
Scientific Reports     Open Access   (Followers: 10)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 15)
Sensor Letters     Full-text available via subscription   (Followers: 1)
Sensors and Actuators A: Physical     Hybrid Journal   (Followers: 20)
Services Computing, IEEE Transactions on     Hybrid Journal   (Followers: 3)
Shock and Vibration     Hybrid Journal   (Followers: 7)
Shock Waves     Hybrid Journal   (Followers: 4)
Small     Hybrid Journal   (Followers: 7)
Software Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 21)
Solid State Physics     Full-text available via subscription  
Solid-State Circuits Magazine, IEEE     Hybrid Journal   (Followers: 1)
South African Journal for Research in Sport, Physical Education and Recreation     Full-text available via subscription   (Followers: 3)
Space Research Journal     Open Access   (Followers: 2)
Space Weather     Full-text available via subscription   (Followers: 3)
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy     Hybrid Journal   (Followers: 7)
Spectrochimica Acta Part B: Atomic Spectroscopy     Hybrid Journal   (Followers: 4)
Spectroscopy     Hybrid Journal   (Followers: 3)
Spectroscopy Letters: An International Journal for Rapid Communication     Hybrid Journal   (Followers: 3)
Sri Lankan Journal of Physics     Open Access  
Strain     Hybrid Journal   (Followers: 2)
Strength of Materials     Hybrid Journal   (Followers: 3)
Strength, Fracture and Complexity     Hybrid Journal   (Followers: 1)
Structural Dynamics     Open Access  
Studies In Applied Mathematics     Hybrid Journal   (Followers: 1)
Superconductor Science and Technology     Hybrid Journal   (Followers: 1)
Surface Engineering     Hybrid Journal   (Followers: 3)

  First | 1 2 3 4 5 6 | Last

Journal Cover physica status solidi (c)
   [3 followers]  Follow    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 1862-6351 - ISSN (Online) 1610-1642
     Published by John Wiley and Sons Homepage  [1602 journals]   [SJR: 0.397]   [H-I: 27]
  • Effect of iron on the dielectric properties of silicate glasses prepared
           by sol‐gel
    • Authors: S. A. Salehizadeh; M. P. F. Graça, M. A. Valente
      Pages: n/a - n/a
      Abstract: The sol‐gel method is a very flexible route for producing sieving matrix such as SiO2 with pore radii in nanoscale region to embed oxide particles like Fe2O3. In this work, iron oxide nanoparticles embedded in a SiO2 glassy matrix prepared by the sol‐gel method have been investigated as a function of Fe/Si ratio. Different composition of dried gels with 1, 2, 10 and 20 mol% of Fe2O3 in the SiO2 matrix were heat‐treated (HT) in air, at temperatures from 400 ºC up to 1400 °C. The structure and morphology of the obtained glasses and glass‐ceramics were studied by X‐ray powder diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). Impedance spectroscopy measurements and magnetic characterization were performed as function of temperature and the results are related with the microstructure. The X‐ray diffraction patterns showed that increasing the amount of Fe2O3 oxide promotes the formation of crystalline phases, in particular silicate phases. The increase of the heat‐treatment temperature has a similar behavior. The electrical and dielectric properties were related with these structural modifications and with the sample morphology. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-26T06:10:21.942599-05:
      DOI: 10.1002/pssc.201400015
       
  • Annealing related changes in near‐edge absorption and structural
           properties of Al‐doped ZnO thin films
    • Authors: S. Schönau; F. Ruske, S. Neubert, B. Rech
      Pages: n/a - n/a
      Abstract: In order to clarify the origin of the previously reported reduction of sub‐band gap absorption of sputtered ZnO:Al films upon thermal annealing and raising deposition temperature, structural characterization using Ra‐man spectroscopy was carried out on various films. Correlation of the Urbach energy to the FWHM of the E(high)2 mode was found. Oxygen addition to the film growth did not result in changes of the Urbach energy, despite pronounced changes of the electrical properties. The results suggest that extended defects, rather than intrinsic point defects, give rise to the sub‐band gap absorption. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-26T06:10:21.028944-05:
      DOI: 10.1002/pssc.201400002
       
  • Kinetic parameters of Cd1‐x‐yMnxZnyTe alloys melting and
           crystallization processes
    • Authors: V. Kopach; O. Kopach, P. Fochuk, L. Shcherbak, A. Bolotnikov, R. B. James
      Pages: n/a - n/a
      Abstract: The knowledge about parameters of melting and crystallization processes is required for controlled growth of ternary or quaternary single crystals from the melts. The differential thermal analysis method was used for investigation of the melting and crystallization kinetic parameters of Cd1‐x‐yMnxZnyTe alloys (x = 0.05–0.25, y = 0.05, 0.10). Two different ways of sample thermal processing allow us to study the supercooling‐superheating dependencies and the volume fraction of quasi‐solid phase (clusters) depending on the melt holding temperature and time. “Negative” supercooling of Cd1‐x‐yMnxZnyTe melts was observed when superheating of the melts don't exceed 20 K after their melting start. The su‐ percooling values of Cd1‐x‐yMnxZnyTe melts decreased with increasing x (i.e. Mn content). The change of the melts holding time from 10 to 60 min has no effect on the supercooling values. Volume fraction of Cd1‐x‐yMnxZnyTe alloys clusters existing in the melt decreased with the holding temperature increasing. Full homogenization occurred only after of Cd0.95‐xMnxZn0.05Te melts superheating higher than 1385 K, below this temperature melts exist in semiliquid state. The volume fraction of the quasi‐solid phase is smaller if the melt was heated at 10 K/min than after heating at 5 K/min to the same temperature. Melting temperature of Cd0.95‐xMnxZn0.05Te alloys decreased with Mn content increasing. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-26T06:10:20.120683-05:
      DOI: 10.1002/pssc.201300660
       
  • Modeling and multifractal analysis of radiation defect evolution in solids
    • Authors: Kazbek Baktybekov; Aliya Baratova
      Pages: n/a - n/a
      Abstract: The results of modeling of radiation defects formation and evolution on the surface and in the volume of a crystal are presented in this paper. Statistical properties are calculated for the investigated system. It is revealed that defect structure is a multifractal and system entropy decreases, while observing self‐organization of the physical system. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-20T07:23:11.964285-05:
      DOI: 10.1002/pssc.201400005
       
  • Issue Information: Phys. Status Solidi C 5–6/2014
    • Pages: n/a - n/a
      PubDate: 2014-05-19T03:46:47.026694-05:
      DOI: 10.1002/pssc.201470050
       
  • Cover Picture: Phys. Status Solidi C 5–6/2014
    • Pages: n/a - n/a
      Abstract: Biocompatible magnetic nanoparticles have emerged as promising agents to be used in clinical applications including diagnosis by resonance imaging, drug delivery, and also selective destruction of tumors by hyperthermia. In this regard, despite many advanced synthesis methods have been developed to fabricate magnetic colloids, they usually result in small amounts of material, which are insufficient for most practical applications. Martinez‐Boubeta and co‐workers have fabricated relatively large (grams per hour) amounts of basalt‐derived nanoparticles (see pp. 1053–1058). They used solar furnace facilities in the Pyrénées‐Orientales in France to evaporate igneous rocks taken from the warm island of Lanzarote, with quite encouraging preliminary results. Not only do these basalt‐derived nanoparticles resemble bioactive materials, but also they are magnetic and have the ability to act as thermoseeds for cancer treatment using hyperthermia. To the best of our knowledge, this is the first reportedly work dealing with the development of magnetic nanoparticles from natural rocks abundant within the Earth's crust, and furthermore, using a facile, environmental friendly and cost effective process.The background photograph of the cover picture was adapted with permission from Björn Höfling.
      PubDate: 2014-05-19T03:46:45.457294-05:
      DOI: 10.1002/pssc.201470049
       
  • Influence of annealing on the properties of (Cd,Mn)Te crystals
    • Authors: M. Witkowska‐Baran; D. M. Kochanowska, A. Mycielski, R. Jakieła, A. Wittlin, W. Knoff, A. Suchocki, P. Nowakowski, K. Korona
      Pages: n/a - n/a
      Abstract: Semiinsulating (Cd,Mn)Te crystals are believed to be suitable to successfully replace the commonly used (Cd,Zn)Te and CdTe crystals as a material for manufacturing large‐area X‐ and γ‐ray detectors. The purpose of the studies was to elaborate the technology of the (Cd,Mn)Te crystal plates with high resistivity, uniform in the whole volume of the plate. The article presents a method of annealing of the monocrystalline (Cd,Mn)Te crystal plates, giving the desired, repeatable results. The semiinsulating (Cd,Mn)Te crystals, doped (for compensation) mainly by vanadium, but sometimes by Cl, In, or Cl and V, were grown by the Bridgman method, and the monocrystalline plates were cut. Subsequently the plates were annealed in Cd vapour. The resistivity of the plates was around 109 Ωcm, and the μτ‐product was about 10‐4 ‐10‐3 cm2/V. Mapping of the resistivity was performed on both the as‐grown crystals and the annealed crystal plates. The resistivity of the as‐grown crystals was in the range of 105‐106 Ωcm and inhomogeneous. After annealing the resistivity increased up to 109 Ωcm and better homogeneity could be seen. Annealing in the saturated Cd vapour influenced tellurium inclusions/precipitates. It was studied by IR transmission microscopy. For the as‐grown samples the density of Te inclusions (>1 µm) was ≈ 4×105 cm‐3, but for the annealed samples it was ≈ 104 cm‐3. The low‐temperature photoluminescence (PL) measurements indicated significantly lowered concentrations of acceptors after annealing. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:20:08.412358-05:
      DOI: 10.1002/pssc.201300746
       
  • Galvanomagnetic and thermoelectric properties of Te doped
           single‐crystal bismuth wires
    • Authors: A. A. Nikolaeva; L. A. Konopko, T. E. Huber, A. K. Tsurkan, D. F. Meglei, D. Yu. Matveev
      Pages: n/a - n/a
      Abstract: We present a study of the electrical, transport and thermoelectric properties of Te‐ doped single‐ crystal Bi wires in a glass capillary. The tellurium concentration ranged up to the solubility limit. Measurements of resistance and thermopower were carried out over a wide range of temperatures (2–300 K) and magnetic fields (0–14 T). The shift of the Fermi level by Te doping of Bi wires is calculated from the Shubnikov de Haas oscillations. The effect of quantum confinement and the wire boundary scattering at low temperatures is significantly suppressed for Te‐ doped samples, which are consistent with general theoretical considerations. An anomaly of the thermopower in the form of sign inversion from negative to positive was detected at an electron concentration of ∼1×1020 cm‐3. The observed anomaly disappears after further doping. The effect is interpreted in terms of the manifestation of the features in thermopower at an electronic topological transition (2 1/2 Lifshitz impurity phase transition). (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:10:21.673676-05:
      DOI: 10.1002/pssc.201300192
       
  • Thermoelectric properties of Bi2Te3 microwires
    • Authors: L. A. Konopko; A. A. Nikolaeva, T. E. Huber, D. F. Meglei
      Pages: n/a - n/a
      Abstract: We present here a study of electrical and thermoelectric properties of n ‐ and p ‐Bi2Te3 microwires (n ‐type Bi2Te2Se; p ‐type Bi0.5Sb1.5Te3) with different diameters (d =10–20 µm). Cylindrical Bi2Te3 crystals with glass coating were prepared by the liquid phase casting in a glass capillary. The X‐ray studies have shown that the microwire core is in general polycrystal consisting of big disoriented single crystal blocks. Measurements of resistance and thermopower were carried out over a wide range of temperatures (4.2–300 K) and magnetic fields (0–14 T). At 300 K for samples of n ‐ and p ‐type the thermopower S and power factor P.f. = S2σ were (100–140) µV/K, 1.6×10‐3 W/(K2m) and (150–300) µV/K, 4.5×10‐3 W/(K2m), respectively. Magnetic field dependences of Power factor were measured at various temperatures (T =35, 100, 270 K) and different magnetic field orientations. A broad maximum is the dominant feature of the magnetic field dependence of power factor for p‐ type samples, while power factor decreases for n‐ type samples. We have obtained maximum power factor P.f. =6.8×10‐3 W/(K2m) for p ‐type sample at longitudinal magnetic field B =3 T at T =100 K. Shubnikov de Haas oscillations with equal periods ΔB =0.038 T‐1 both in longitudinal and transverse magnetic fields for carriers with mc = 0.15m0 in p ‐type Bi2Te3 microwire were observed. These oscillations could arise from the topological surface states. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:10:20.667512-05:
      DOI: 10.1002/pssc.201300202
       
  • Photoluminescence study of γ‐irradiation effect on the defect
           structure in Ge‐doped CdTe single crystals
    • Authors: Iu. Nasieka; L. Rashkovetskyi, M. Boyko, V. Strelchuk, Z. Tsybrii, B. Danilchenko, L. Shcherbak
      Pages: n/a - n/a
      Abstract: An effect of γ‐irradiation in the dose range 10‐500 kGy on the defect structure of Ge‐doped CdTe single crystals (CdTe:Ge) was investigated via the method of low‐temperature photoluminescence. It was obtained that γ‐irradiation in mentioned above dose range leads to the substantial decreasing of intensities of excitonic emission bands – D0X, A0X, VDX and increase in the intensities of impurity‐related emission bands – eA1,eA2, DA. It was shown that such changes in the luminescence can be explained by radiation‐stimulated redistribution of luminescence centers between recombination channels. The latter includes vacancy‐type defects filling by Ge dopant atoms which leads to the improving of the crystalline perfection of irradiated CdTe:Ge crystals. Mentioned material quality increasing was confirmed analysing the electron‐LO‐phonon coupling in irradiated crystals which was characterized via the Huang‐Rhys factor for corresponding luminescence bands. For the verification of the assumption about radiation‐stimulated compensation of native defects the resonant Raman measurements also were carried out. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:10:19.789265-05:
      DOI: 10.1002/pssc.201300571
       
  • Raman investigation on thin and thick CdTe films obtained by close spaced
           vacuum sublimation technique
    • Authors: D. Nam; H. Cheong, A. S. Opanasyuk, P. V. Koval, V. V. Kosyak, P. M. Fochuk
      Pages: n/a - n/a
      Abstract: The CdTe thin and thick films were obtained by the close spaced vacuum sublimation technique on a glass substrate under the following growth conditions: the evaporator temperature was 620 °C; and the substrate temperature was varied in the range from 250 °C to 550 °C. High purity CdTe powder was used as a charge for evaporation. The Raman spectra were measured using TRIAX 320 and TRIAX 550 spectrometers at room temperature. The 488‐nm line and 514.5‐nm line of an Ar+ laser and a 785‐nm diode laser were used as excitation sources. The signal was collected by the liquid nitrogen cooled charge‐coupled‐device (CCD) detector. A number of intense Raman peaks at 140, 167, 190, 271, 332 and 493 cm‐1 were observed and were interpreted as TO (140 cm‐1), 1LO (167 cm‐1), 2LO (332 cm‐1), 3LO (493 cm‐1) phonon modes and plasmon‐phonon mode (190 cm‐1). The presence of several phonon replicas in the Raman spectra confirms high crystal quality of the samples. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:10:18.985556-05:
      DOI: 10.1002/pssc.201300577
       
  • Self‐compensation limited conductivity of Cl‐doped CdTe
           crystals
    • Authors: O. L. Maslyanchuk; L. A. Kosyachenko, S. V. Melnychuk, P. M. Fochuk, T. Aoki
      Pages: n/a - n/a
      Abstract: The conductivity of semi‐insulating Cl‐doped CdTe crystals produced by Acrorad Co. Ltd. with a resistivity ρ = (3‐6)×109 Ω·cm (300 K) was investigated. It is shown that the Fermi level in the band gap is located below the Fermi level in intrinsic CdTe which indicates the hole conductivity of the material. The concentration of holes in the studied crystals is determined to be 2‐3 orders of magnitude higher than the concentration of electrons. The statistics of electrons and holes in a semi‐insulating semiconductor containing self‐compensation complexes (centers) is considered bearing in mind that the effect of background impurities and defects in heavily Cl‐doped CdTe crystal is strongly reduced. A method for determining the ionization energy and the compensation degree of deep donors contained in the complexes was applied. It is shown that virtually intrinsic conductivity of the studied CdTe crystals is provided by the donors with ionization energy 0.68‐0.69 eV, whose level is located at 0.05‐0.06 eV above the middle of the band gap. Due to strong compensation, the Fermi level turns out below the middle of the band gap. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:10:18.072856-05:
      DOI: 10.1002/pssc.201300694
       
  • Studies of the surface regions of (Cd,Mn)Te crystals
    • Authors: Dominika Kochanowska; Marcin Rasiński, Marta Witkowska‐Baran, Małgorzata Lewandowska, Andrzej Mycielski
      Pages: n/a - n/a
      Abstract: The growth process conditions affect quality of the crys­tal. Structural defects such as grains, twin boundaries and precipitates are formed during the crystal growth. The defects (especially‐inclusions) at the surface can be investigated in a microscale by the scanning electron microscopy (SEM). It is shown in the article that a well known etchant, usually used for visual inspection of the quality of the CdTe‐related crystals, can be applied to the preparation of the (Cd,Mn)Te surface for SEM investigations. Samples, cut from different parts of a (Cd,Mn)Te crystal, were ground, mechano‐chemically polished, and treated by the special etchant (to indicate polarity and to reveal twinning). After that treatment the defects (grain and twin boundaries, tellurium inclusions) at the surface became much more accessible for both SEM and visual investigations. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-14T05:10:17.056833-05:
      DOI: 10.1002/pssc.201300711
       
  • LEDs based on p‐type ZnO nanowires synthesized by electrochemical
           deposition method
    • Authors: V. Kapustianyk; B. Turko, I. Luzinov, V. Rudyk, V. Tsybulskyi, S. Malynych, Yu. Rudyk, M. Savchak
      Pages: n/a - n/a
      Abstract: The data concerning the light‐emitting diodes based on ZnO homojunction with ITO/n ‐ZnO/p ‐ZnO+photoresist/Au/Ti and ITO/n ‐ZnO/p ‐ZnO+pho‐toresist+PEDOT:PSS/Au/Ti structures are reported. The p ‐ZnO nanowires were grown by electrochemical deposition method. It is suggested that the p ‐type conductivity first of all is connected with the zinc vacancies VZn. The clear rectifying behavior was observed on the current‐voltage curve of the ZnO p ‐n homojunction. The broad electroluminescence (EL) emission bands in the blue, green and red regions lead to observation of the white light by a naked eye under forward bias. The intrinsic defects such as Zni, VZn, Vo and Oi would be responsible for occurrence of these bands. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-07T06:30:10.579816-05:
      DOI: 10.1002/pssc.201300671
       
  • Structural, electrical and optical properties of zinc‐iridium oxide
           thin films deposited by DC reactive magnetron sputtering
    • Authors: Martins Zubkins; Roberts Kalendarev, Jevgenijs Gabrusenoks, Kaspars Vilnis, Andris Azens, Juris Purans
      Pages: n/a - n/a
      Abstract: ZnO‐IrO2 thin films were deposited on glass by DC reactive magnetron sputtering at room tem‐perature. Structural, electrical and optical properties were investigated as a function of iridium atomic concentra‐tion in the films. XRD data shows that ZnO‐IrO2 thin films are X‐ray amorphous and Raman spectrum resembles the spectrum of IrO2, without any distinct features of wurtzite ZnO structure. The lowest film resistivity and the highest transmittance achieved in the present study were 1.4 × 10‐3 Ωcm and 33% at 550 nm, respectively. However, resistivity and transmittance are inversely related to the iridium concentration in the films.
      PubDate: 2014-05-07T06:23:11.504355-05:
      DOI: 10.1002/pssc.201300653
       
  • Influence of annealing in Zn vapor on the luminescence of MgZnO ceramics
    • Authors: I. Markevich; T. Stara, O. Kolomys, A. S. Romanyuk, V. Strelchuk
      Pages: n/a - n/a
      Abstract: ZnO‐based compounds that exhibit a number of strongly overlapping emission bands in visible spectral region are promising materials for white‐light emitters with continuous emission spectrum. Defect‐related emission in doped with different impurities ZnO, however, spreads from green to red spectral region, so its shift toward shorter wavelengths is required. We supposed that this problem can be solved due to broadening of ZnO band gap by alloying ZnO with MgO. The enhancement of visible emission brightness is also an important problem. In this work, MgxZn1‐xO ceramics with x =0 and x=0.2 were sintered both in air and Zn vapor at 950 oC. Emission and Raman scattering spectra were measured at 300 K using 325 nm line of He‐Cd laser as excitation source. In samples sintered in air, bright UV emission and weak visible one took place, adding MgO to ZnO resulting in blue‐shift of the latter. Sintering in Zn vapor was found to weaken UV emission and to increase drastically the brightness of visible one especially in blue‐green spectral region. As a result, bright blue radiation was observed from MgZnO ceramics under excitation by considerably week UV light. Obtained effects were accounted for by the shift of “green” centers energetic level with respect to involved band edge as a result of band‐gap broadening and by the increase of this center density due to annealing in Zn vapor. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-07T06:23:10.54456-05:0
      DOI: 10.1002/pssc.201300647
       
  • Influence of doping precursor on band gap and morphologies of
           sol‐gel deposited ZnMgO thin films
    • Authors: Amanpal Singh; Sonia Saini, Dinesh Kumar, P. K. Khanna, Mukesh Kumar, B. Prasad
      Pages: n/a - n/a
      Abstract: Zn1–xMgxO thin films were deposited by sol–gel route on p–type Si (100) and quartz substrates. It is ob‐served that the incorporation of Mg and morphological features of the sol–gel derived Zn1–xMgxO thin films extremely depend upon the selection of doping (Mg) precursor salts. Investigation of different doping precursors such as magnesium acetate, magne‐sium chloride and magnesium nitrate have been carried out. Zn1–xMgxO (x = 0.15) thin films deposited us‐ing each doping source were annealed at 300, 500, 700 and 900 °C in the presence of oxygen for one hour. The results showed that the magnesium nitrate required lower annealing temperature and provided good quality of films, However traces of N were observed in the films. The surface morphology and microstructure of the depos‐ited thin films were analyzed by atomic force microscopy. The crystallite dimension, shape and the growth rate were found to be significantly affected by dopant precursors. The chemical compositions were determined by elemen‐tal dispersive spectra. The band gap modulation is stud‐ied by varying the magnesium content from x = 0.00 to 0.40 for each type of salt for Mg doping. The Zn1–xMgxO films deposited using magnesium chloride exhib‐ited poor band gap modulation and lower quality of mi‐crostructure. The films deposited using magnesium ace‐tate exhibited minimum defects, good crystallinity and higher band gap modulation. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-07T06:20:21.788418-05:
      DOI: 10.1002/pssc.201300593
       
  • Optical and structural properties of Al2O3/ZnO nanolaminates deposited by
           ALD method
    • Authors: Adib Abou Chaaya; Roman Viter, Ieva Baleviciute, Mikhael Bechelany, Arunas Ramanavicius, Donats Erts, Valentyn Smyntyna, Philipe Miele
      Pages: n/a - n/a
      Abstract: We report on the investigation of optical and structural properties of Al2O3/ZnO nanolaminates. The nanolaminates were deposited on Si and glass substrates by Atomic layer deposition method. Structural properties of nanolaminates were studied by SEM, GIXRD, and AFM. Optical characterization was performed by transmittance and photoluminescence spectroscopy. Complex analysis of monolayer properties was done by ellipsometry. Optical constants for Al2O3 and ZnO monolayer were calculated.
      PubDate: 2014-05-07T06:20:20.87946-05:0
      DOI: 10.1002/pssc.201300607
       
  • Local structure and dynamics of wurtzite‐type ZnO from
           simulation‐based EXAFS analysis
    • Authors: Janis Timoshenko; Andris Anspoks, Aleksandr Kalinko, Alexei Kuzmin
      Pages: n/a - n/a
      Abstract: Conventional methods of EXAFS data analysis are often limited to the nearest coordination shells of the absorbing atom due to the difficulties in accurate accounting for the so‐called multiple‐scattering effects. Besides, it is often difficult to resolve the non‐equivalent groups of atoms in a single coordination shell due to strong correlation between structural parameters. In this study we overcome these problems by applying two different simulation‐based methods, i.e., classical molecular dynamics (MD) and reverse Monte with evolutionary algorithm (EA), to the analysis of the Zn K‐edge EXAFS data for wurtzite‐type bulk ZnO. The RMC/EA‐EXAFS method allowed us to separate the contributions of thermal disorder and the effect of noncentrosymmetric zinc oxide structure, being responsible for its piezoelectrical and pyroelectrical properties. The MD‐EXAFS method allowed us to test the accuracy of several available force‐field models, which are commonly used in the MD simulations of ZnO nanostructures.
      PubDate: 2014-05-07T06:20:20.0518-05:00
      DOI: 10.1002/pssc.201300615
       
  • Optical and electrical studies of transparent conductive AZO and ITO
           sputtered thin films for CIGS photovoltaics
    • Authors: R. A. Mereu; S. Marchionna, A. Le Donne, L. Ciontea, S. Binetti, M. Acciarri
      Pages: n/a - n/a
      Abstract: Due to the many advantages of aluminum doped zinc oxide (AZO) as an alternative to indium tin oxide (ITO), the optical and electrical properties of AZO thin films deposited on large substrates by D.C. pulsed magnetron sputtering have been investigated in view of future industrial applications. In order to evaluate the effectiveness of AZO thin films as transparent conductive oxide (TCO), their properties have been compared with those of standard ITO grown with the same technique. The effect of the thickness on the optical properties revealed higher transmittance values for AZO (T>86 %) than for ITO (T>83 %) films. The best resistivity values obtained for AZO were about 9.7×10–4 Ωcm versus 5.09×10–4 Ωcm measured for ITO films. Moreover, it was observed that the film resistivity is significantly influenced by the working pressure in the case of AZO films while the ITO resistivity appears almost unaffected. Finally, since both the optical and electrical properties are influenced by the film thickness, it was crucial to determine the proper AZO thickness in order to obtain the optimum of electrical and optical properties for the photovoltaic applications. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-07T06:20:19.187917-05:
      DOI: 10.1002/pssc.201300631
       
  • Concentration determination and activation of rare earth dopants in zinc
           oxide thin films
    • Authors: A. Ziani; A. Tempez, C. Frilay, C. Davesnne, C. Labbé, Ph. Marie, S. Legendre, X. Portier
      Pages: n/a - n/a
      Abstract: In this paper, we will present the development of rare‐earth (RE) doped zinc oxide (ZnO) films for white light emitting diodes (LED). We will present the structural changes of these films as well as their optical properties and associated photoluminescence before and after rapid thermal treatments. We will report depth profile results from plasma profiling time of flight mass spectrometry (PP‐TOFMS) giving the distributions and concentrations of the different elements in the films. We will correlate depth profile and luminescence data to understand the RE emission mechanisms in ZnO matrix. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-07T06:20:18.382059-05:
      DOI: 10.1002/pssc.201300636
       
  • Influence of deposition parameters on ZnO and ZnO:Al thin films
    • Authors: Nilufer Evcimen Duygulu; Alp Osman Kodolbas, Ahmet Ekerim
      Pages: n/a - n/a
      Abstract: Zinc oxide (ZnO) and 2% aluminium doped ZnO (ZnO:Al) thin films were deposited on glass by using r.f. magnetron sputtering without intentional heating. The r.f. power was varied in the range of 150 W to 175 W and process gas (argon) pressure was changed from 0.20 Pa to 0.60 Pa in small variation ranges to identify the influence of sputtering parameters. Achieved results were analysed with the help of XRD, AFM, SEM, HRTEM, four point probe, optical transmittance measurement techniques. According to the results, 165 W was selected as optimum r.f. power value, while 0.20 Pa for ZnO and 0.30 Pa for ZnO:Al thin films were determined as argon gas pressure values. All the thin films were oriented with the crystallographic c‐(002) axis perpendicular to the substrate surface. Moreover, at this deposition values; the resistivity was measured as around 10‐3Ω.cm, while the deposition rate showed variations. The optical transmittance of ZnO:Al was obtained (85%) higher than ZnO (75%) thin film. The optical band gap was changed from 3.45 eV to 4.2 eV. Surface roughness (RMS) values were obtained as 5.44 nm for ZnO and as 2.36 nm for ZnO:Al. (© WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-07T06:20:17.60807-05:0
      DOI: 10.1002/pssc.201300640
       
  • Contents: Phys. Status Solidi C 5–6/2014
    • Pages: 961 - 964
      PubDate: 2014-05-19T03:46:48.596094-05:
      DOI: 10.1002/pssc.201470051
       
  • Nanoscaled Magnetism and Applications
    • Authors: Arcady Zhukov
      Pages: 965 - 967
      Abstract: This issue collects the proceedings of the Donostia International Conference on Nanoscaled Magnetism and Applications (DICNMA 2013). The DICNMA 2013 conference was held at the Miramar Palace between 9th and 13th September, 2013. It was organized with three daily parallel sessions. 330 abstracts from 36 countries have been submitted, of which about 280 were presented at the conference. It is worth mentioning that during the last 15 years we organized several international conferences, such as Magnetism of Nanophase Materials (1998), Recent Research on Novel Magnetic Structures and Their Applications (2000), International Workshop on Magnetic Wires (2001), Third Joint European Magnetic Symposia, JEMS‐2006, International Workshop on Magnetic Wires (2008), and Recent Trends on Nanomagnetism, Spintronics and Applications (RTNSA‐2011). Consequently, we organized DICNMA 2013 continuing the tradition of holding international scientific events in San Sebastián. Moreover, in organizing DICNMA 2013 we wanted to cover all aspects of the previous conferences. Consequently, the conference has provided a forum for the magnetism community to discuss new concepts, properties and developments in all branches of fundamental and applied magnetism, as well as on magnetic materials and their applications. We are grateful to the major contribution from the worldwide community of magnetism. The Program Committee consisted of all topical session chairs with their active participation on selection of works presented at the conference. The conference program composed of two plenary and six semiplenary talks, 75 invited talks and 101 selected oral talks, which were arranged with three parallel oral sessions in addition to two poster sessions with 82 presentations. We are grateful for their hard work and dedication for the selection of very high level presentations and their harmonic sequence in the sessions. We are especially grateful to Prof. Albert Fert, Nobel laureate, who gave a plenary talk on Monday 9th September, 2013, Prof. Stuart Parkin who gave another plenary talk and to other distinguished plenary and semi‐plenary speakers. More than 60 full text papers were submitted for the special issue; after peer review, 56 papers were accepted for publication in the proceedings of the conference. All papers have been refereed in accordance with regulations of the physica status solidi (a) and (c) journals. We hope that this special issue of physica status solidi (a) and (c) will provide a unique opportunity for many researchers, who are involved in different areas of magnetism of modern magnetic materials to share new ideas and concepts in this research field and favoring different discussions about the future basis and perspectives on the entire field and potential technological applications for the industry. We hope that this issue will bring interesting information to the readers and will be useful for people involved in this subject of scientific research. We are very pleased to have worked with Wiley as the publisher of the conference proceedings with special thanks to Stefan Hildebrandt. On behalf of the organizing and international advisory committees I would like to thank the invited speakers, reviewers and the authors who have made contributions for their cooperation, which has made the conference a really international one with a unique success. I would also like to thank Sofia Zhukova and Paola Benito for invaluable efforts for the conference organization as the general secretaries. We are grateful to the Conventional bureau of San Sebastián for the financial support and Summer School of the Basque Country University for the support and continuous attention. The immensely rich and diverse scientific program composed of topical sessions that were proposed by excellent scientists working in corresponding fields of magnetism. The focused sessions are given below with corresponding session organizers' names. Without their active involvement, invaluable contribution and support, this conference could not have been a real success. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-05-19T03:46:48.469237-05:
      DOI: 10.1002/pssc.201470052
       
  • Inverse problem method for complex permittivity reconstruction of layered
           media in a rectangular waveguide
    • Authors: Yu. G. Smirnov; Yu. V. Shestopalov, E. D. Derevyanchuk
      Pages: 969 - 974
      Abstract: We solve the inverse problem of finding frequency‐dependent complex permittivity of a multi‐sectional dielectric diaphragm in a waveguide of rectangular cross section from the transmission coefficient measured at different frequencies. Based on the developed recursive method we perform a detailed analysis for one‐, two‐ and three sectional diaphragms. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:15.351226-05:
      DOI: 10.1002/pssc.201300697
       
  • Magnetism induced by iron impurities in the overdoped superconductor
           La2–xSrxCuO4
    • Authors: A. K. Arzhnikov; L. V. Dobysheva
      First page: 975
      Abstract: We have performed first‐principles calculations of the magnetic properties of the overdoped (x=0.25) LSCO and Fe‐LSCO systems. Originally, without impurities of iron, La1.75Sr0.25CuO4 is nonmagnetic. Replacing one of Cu atoms in a unit cell with an Fe atom (3 or 6 % of Fe relatively to the Cu content) results in lowering the total energy of the magnetic state in comparison to the nonmagnetic one. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-10T05:42:05.543323-05:
      DOI: 10.1002/pssc.201300619
       
  • Investigation of structural and magnetic properties of Heusler
           Fe2+xMn1−xAl alloys by first principles method
    • Authors: V. D. Buchelnikov; M. A. Zagrebin, V. V. Sokolovskiy, I. A. Taranenko, A. T. Zayak
      First page: 979
      Abstract: Heusler alloys Fe2+xMn1−xAl exhibit intricate interplay between structural parameters and a number of competing magnetic states. In this work, we use first principles calculations to investigate crystal lattice relaxation of these alloys and their coupling to the magnetic order, with a particular focus on the tetragonal distortions characterised by the c/a ratio. We find that the calculated equilibrium cubic phase is antiferromagnetic, while a metastable ferrimagnetic state is also present, being higher in energy only by an order of kT, suggesting a close competition of these two magnetic states in real materials. The ferrimagnetic state corresponds better to the experimental data. The tetragonal distortions and the changes of volume alter dramatically the balance in magnetic coupling by favouring the ferromagnetic state. In order to understand this magneto‐structural coupling, we obtained (a, c/a) diagrams that show regions of relative stability of the ferromagnetic and antiferromagnetic states Our calculations suggest an opportunity for tuning magnetic properties of Fe2+xMn1−xAl alloys with strain and composition. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-15T04:10:24.688713-05:
      DOI: 10.1002/pssc.201300719
       
  • Influence of magnetic nanotube thickness on the field behaviour of the
           confined transverse wall
    • Authors: A. P. Chen; J. Gonzalez, K. Y. Guslienko
      Pages: 984 - 985
      Abstract: For two magnetic nanotubes with radius, R= 100 nm, length L= 800 nm and tube thickness ΔR (difference of the outer and inner tube radii) being, respectively, 30 nm and 40 nm, the transverse walls (TW) are formed in the tube cross‐section ΔR ×L in the middle part of tube. The responses of the TW confined in these two nanotubes to the magnetic fields applied along the easy axis of the tube and induced in the circular direction had been studied by using 2D micromagnetic simulation method. The results of simulations show that only 10 nm difference in nanotubes thickness can cause very different field behaviors for the confined TW in both the magnetic fields directions. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:20.901947-05:
      DOI: 10.1002/pssc.201300698
       
  • GHz magnetic field influence on magnetization reversal in amorphous
           microwires
    • Authors: A. Chizhik; M. Ipatov, A. Stupakiewicz, A. Zhukov, A. Maziewski, J. Gonzalez
      First page: 986
      Abstract: This work is devoted to the study of the magnetization reversal in the Co‐rich glass covered microwire with nearly‐zero magnetostriction in the presence of super high frequency (SHF) (about 1 GHz) circular magnetic field that is important for the elucidation of GMI mechanism. Magnetic domain imaging has been performed by means of magneto‐optical Kerr effect (MOKE) polarizing microscopy. Local hysteresis loops were obtained from the magneto‐optic intensity as a result of images processing. The increase of the SHF field amplitude causes the change of the magnetization reversal mechanism – the rotation of the magnetization dominates. Also the hysteresis loop has an asymmetric shape that confirms the competition between stable and meta‐stable helical magnetic states. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-10T05:42:06.752132-05:
      DOI: 10.1002/pssc.201300748
       
  • Magnetism of 2d Heisenberg classical square lattices: theory vs
           experiments
    • Authors: Jacques Curély; Janis Kliava
      Pages: 989 - 994
      Abstract: In this article, we exclusively focus on the low‐temperature behaviors of 2d square lattices composed of (2N +1)2classical spins with isotropic couplings between first‐nearest neighbors (Heisenberg couplings), in the thermodynamic limit (N →+∞). After briefly recalling the theoretical closed‐form expressions derived for (i) the zero‐field partition function ZN (0), (ii) the spin‐spin correlation between any two lattice sites, (iii) the correlation length and (iv) the static susceptibility, we build up a diagram characterized by three low‐temperature magnetic phases. Moreover we show that the behaviors of these physical quantities as well as the diagram are in perfect agreement with the corresponding ones derived using a renormalization method. Finally we give criterions allowing to directly determine the magnetic phases characterizing 2d magnetic compounds described by our microscopic model. An experimental test is given for illustrating this theoretical study. It allows one to obtain a perfect fit of the susceptibility of [{Mn(DENA)2(N3)2}n] (DENA is the ligand diethylnicotinamide). (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:11.424506-05:
      DOI: 10.1002/pssc.201300734
       
  • An idea of the test stand for studies of magnetobarocaloric materials
           properties and possibilities of their application
    • Authors: A. Czernuszewicz; J. Kaleta, D. Lewandowski, M. Przybylski
      Pages: 995 - 999
      Abstract: The paper presents an idea of the laboratory test stand for evaluation of the application potential of magnetobarocaloric materials. These materials are characterized by the temperature change under stimulation by a magnetic field and mechanical loading. This property of the material can be used for construction of cooling and heating devices. Thanks to the ecofriendly character of the solutions based on this material it may replace, in the near future, nowadays solutions based on the gas compression–decompression method. The presented laboratory test stand will allow comparison of the several groups of materials in terms of their application in modern cooling systems. The paper shows the main ideas behind the construction and working principles of the system. To obtain a change in the temperature of the tested material it will be subjected to the magnetic field generated by permanent magnets and mechanical loading generated with use of a universal testing machine. Loading will cause a uniaxial tension state in the material. Magnetobarocaloric material, working as a refrigerant in the device, will be applied as a multiflow system. The test stand will work in a modified active magnetic regenerator (AMR) cycle that is most commonly used in prototypes of magnetic refrigerators. This cycle will be adapted for the use of mechanical loading in addition to magnetic stimulation. The test stand presented in this paper is currently under construction. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:10.56723-05:0
      DOI: 10.1002/pssc.201300732
       
  • Asymmetric magnetoresistance in bulk In‐based
           off‐stoichiometric Heusler alloys
    • Authors: Igor Dubenko; Tapas Samanta, Abdiel Quetz, Ahmad Saleheen, Valerii N. Prudnikov, Alexander B. Granovsky, Shane Stadler, Naushad Ali
      Pages: 1000 - 1003
      Abstract: It has been found that Ni50Mn35In14B exhibits with increasing temperature a first‐order magnetostructural phase transition from a low‐magnetization martensitic phase to a high‐temperature ferromagnetic austenitic phase at TM∼315 K as observed from magnetization M(T) curves with H=0.05 T. A shift in TM of about 12 K towards lower temperatures has been detected under application of a 5T magnetic field. An asymmetric magnetoresistance (spin‐valve‐like behavior) has been observed in the vicinity of TM at 304 K after the initial application of magnetic field that could be related to the kinetic arrest and de‐arrest of a fractional austenite phase in the vicinity of phase co‐existence. A possible origin of a spin‐valve‐like MR in Ni50Mn35In14B, and its relation to structural, magnetic, and magnetocaloric properties, has been discussed. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:06.899585-05:
      DOI: 10.1002/pssc.201300662
       
  • Biocompatible iron oxide/porous silicon nanocomposite with tunable
           magnetic properties
    • Authors: P. Granitzer; K. Rumpf, P. Poelt, M. Reissner
      Pages: 1004 - 1006
      Abstract: Iron oxide nanoparticles of 5 and 8 nm in size have been infiltrated into the pores of porous silicon. The aim is to create a superparamagnetic (SPM) nanocomposite system with maximized magnetic field induced moment. Therefore the particle size versus the superparamagnetic behaviour has been figured out. The blocking temperature TB which indicates the transition between superparamagnetic behaviour and blocked state is not only dependent on the particle size but also on the magnetic interactions between them which can be varied by the distance between the particles. The magnetic behavior of the nanocomposite has been examined with regard to the magnetic interactions between the particles within the pores. Dependent on the size but also the distance between the particles, which has been adjusted by the various concentrations, TB has been shifted. Furthermore the modification of the porous silicon template results in a change of the transition temperature due to the variation of the particle distance of adjacent pores. To fabricate distinct composite systems suitable in biomedicine the porous silicon template as well as the loading of the pores with the particles has to be adjusted. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:07.094418-05:
      DOI: 10.1002/pssc.201300706
       
  • Boron addition in MnFe(P,Si) magnetocaloric materials: interstitial vs.
           substitutional scenarii
    • Authors: F. Guillou; H. Yibole, G. Porcari, E. Brück
      Pages: 1007 - 1010
      Abstract: The addition of boron in MnFe(P,Si) materials has been studied by considering two possibilities: an interstitial intercalation or a substitutional approach. A cell volume decrease with “extra” B addition is observed which is incompatible with an interstitial scenario. On the contrary, the evolutions of the cell volume, ratio of the cell parameter and Curie temperatures are found to be well consistent with the values already reported for the substitution of phosphorous by boron in the parent Fe2P1‐xBx compound. This work sheds light on the possibility to achieve a fine tuning of the magnetic and magnetocaloric properties of MnFe(P,Si) materials by involving a new parameter: boron substitution. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:11.39532-05:0
      DOI: 10.1002/pssc.201300569
       
  • Effect of asymmetric edgeperturbation and strain on spin‐conduction
           in zigzag graphene nanoribbons
    • Authors: J. P. C. Baldwin; Y. Hancock
      First page: 1011
      Abstract: The role of magnetic asymmetric inhomogeneities in zigzag graphene nanoribbons is studied within the context of a generalised tight‐binding model with mean‐field Hubbard‐U interaction. Perturbing the magnetic strength along one edge of the ribbon and adjusting the ribbonwidth are shown to tune the spin‐conductance and magnetic properties as the uniaxial strain is increased. We demonstrate the closing of the spin‐dependent conductance gap and spin‐selective transmission at the Fermi energy for systems with reduced site‐specific magnetism along the top‐edge of the ribbon. Quantum mechanisms for achieving tunable spin‐conductance as a function of strain are revealed as energy minimisation mechanisms in the model. Such mechanisms may be key in the design of future nanoribbon spintronic devices. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-15T04:10:28.492793-05:
      DOI: 10.1002/pssc.201300654
       
  • Modelling of strain due to martensitic transformation induced by magnetic
           field and stress in NiCoMnIn magnetocaloric alloys
    • Authors: Laurent Hirsinger
      First page: 1016
      Abstract: The principal thermo‐magneto‐mechanical couplings involved in ferromagnetic shape memory alloys are apprehended and modelled. The well‐known (in mechanics) Clausius‐Clapeyron relation is extended to magnetism. A simplified model with internal variables is built in order to predict the hysteresis loops in strain in Ni45Co5Mn36.5In13.5magnetocaloric alloys. This strain is due to (direct and reverse) martensitic transformation induced by both the magnetic field and the mechanical stress. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-15T04:10:27.507419-05:
      DOI: 10.1002/pssc.201400003
       
  • Magnetic shape memory microactuator
    • Authors: E. Kalimullina; A. Kamantsev, V. Koledov, V. Shavrov, V. Nizhankovskii, A. Irzhak, F. Albertini, S. Fabbrici, P. Ranzieri, P. Ari‐Gur
      First page: 1023
      Abstract: Bimetallic composite nanotweezers based on Ti2NiCu alloy with shape memory effect (SME) have been recently proved to allow the manipulation of real nano‐objects, such as nanotubes, and bionanoparticles while heated up to 40‐60 °C by laser radiation. The possibility of developing nanotweezers operating at a constant temperature is of particular importance mainly for the manipulation of biological objects. In this work, a microactuator was produced using a composite bilayer made of a layer of rapidly quenched Ni53Mn24Ga23 ferromagnetic shape memory Heusler alloy and an elastic layer of Pt. The size of the microactuator is 25×2.3×1.7 µm3. The controlled bending deformation of the actuator is 1.2 %, with a deflection of the end of the actuator higher than 2 µm has been obtained by applying a magnetic field of 8 T at T = 62 °C The possibility of the development of new technologies for magnetic‐field‐controlled nanotools operating at a constant temperature using the new multifunction magnetic shape memory alloys will be discussed. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:20.993621-05:
      DOI: 10.1002/pssc.201300718
       
  • Anisotropic magnetoresistance effect of a strong ferromagnet:
           magnetization direction dependence in a model with crystal field
    • Authors: Satoshi Kokado; Masakiyo Tsunoda
      First page: 1026
      Abstract: We theoretically study magnetization direction dependence of the anisotropic magnetoresistance (AMR) effect of a strong ferromagnet. We here use the two‐current model which takes into account the s –d scattering, where s (d) is the conduction state (the localized d states). The d states have the spin–orbit interaction, exchange field, and crystal field of tetragonal symmetry. From the model, we derive analytic expressions of twofold and fourfold symmetric terms of the AMR ratio. The dominant component in the twofold symmetric term is proportional to the difference of partial density‐of‐states (DOS) at the Fermi energy (EF) between dγ and dε orbitals. The fourfold symmetric term is proportional to the difference of partial DOS at EF among dε orbitals. In addition, using the expressions, we analyze an experimental result of the AMR ratio of Fe4N. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:17.66948-05:0
      DOI: 10.1002/pssc.201300736
       
  • Electrically tunable nonreciprocity of microwave transmission through
           “ferrite‐varactor loaded resonant element” planar
           metastructure
    • Authors: G. A. Kraftmakher; V. S. Butylkin, Yu. N. Kazantsev
      Pages: 1033 - 1038
      Abstract: We suggest new planar metastructures “ferrite plate–varactor‐loaded resonant element” that provide voltage tunable nonreciprocity of microwaves transmission in contrast to traditional magnetic control. The effect is observed by tuning varactor capacitance with changing reverse‐bias voltages under the ferromagnetic resonance excitation near the varactor‐loaded element resonance frequency. Wide tuning range has been obtained with nonreciprocity 19 dB between 5.4 and 5.9 GHz. Presented metastructures are useful for the development of quick‐tunable nonreciprocal systems. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:04.654422-05:
      DOI: 10.1002/pssc.201300562
       
  • Pathways for novel magnetocaloric materials: A processing prospect
    • Authors: Maria Krautz; Josef Hosko, K. Skokov, Peter Svec, Mihai Stoica, Ludwig Schultz, Jürgen Eckert, Oliver Gutfleisch, Anja Waske
      Pages: 1039 - 1042
      Abstract: Composites of two magnetocaloric components have been prepared by melt spinning. A special nozzle modification allows to separate the melts of two different materials which solidify simultaneously as rapidly quenched composite. Two materials combinations were chosen: (a) Fe‐based amorphous materials with different Cr‐contents and (b) Fe‐based alloys with different Si‐content resulting in crystalline La(Fe,Si)13 phase with large magnetocaloric effect after subsequent annealing. By melt spinning crystalline segments of several cm length and long amorphous ribbons were obtained. The magnetocaloric properties of the composites were assessed by magnetometry and direct measurements of the adiabatic temperature change. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:09.208838-05:
      DOI: 10.1002/pssc.201300637
       
  • HeLa cells separation using MICA antibody conjugated to magnetite
           nanoparticles
    • Authors: David Lago‐Cachón; Montserrat Rivas, Carlos López‐Larrea, Antonio López‐Vázquez, Graciela Martínez‐Paredes, José A. García
      First page: 1043
      Abstract: Superparamagnetic nanoparticles (MNP) have attracted much interest for medical applications, like magnetic cell separation, magnetic resonance imaging, drug delivery and hyperthermia In this work, 10 nm MNP were functionalized with human α‐MICA antibody, via biotin‐streptavidin conjugation, due to the importance of MICA receptor in antitumor immunity. The potentiality of the nanoparticles has been tested in vitro with two different cell lines: HeLa (with MICA ligands on surface) and HL‐60 (without MICA ligands). MNP tagged HeLa cells were effectively separated by application of a magnetic field gradient. TEM micrographs were performed after magnetic separation, proving intracellular presence of the functionalized MNP. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:18.798665-05:
      DOI: 10.1002/pssc.201300729
       
  • Electronic and magnetic properties of high‐pressure phases in the
           systems Mn–GaSb and Cr–GaSb
    • Authors: Maria Magnitskaya; Erkin Kulatov, Vladimir Baturin, Yurii Uspenskii
      Pages: 1048 - 1052
      Abstract: Ab initio study is reported on the electronic and magnetic properties of high‐pressure‐synthesized compounds M GaSb and M Ga2Sb2 (M = Mn, Cr). Based on comparison of obtained results, we discuss trends in the properties of these systems under change of 3d constituent. It is shown that CrGa2Sb2 stands out among the other compounds due to peculiarities of its electronic structure, which lead to very low and anisotropic conductivity. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:13.086213-05:
      DOI: 10.1002/pssc.201300702
       
  • Scaling up the production of magnetic nanoparticles for biomedical
           applications: cost‐effective fabrication from basalts
    • Authors: C. Martinez‐Boubeta; K. Simeonidis, St. Amarantidis, M. Angelakeris, L. Balcells, C. Monty
      Pages: 1053 - 1058
      Abstract: We report here the first results on magnetic nanoparticles fabricated from basalt fragments of the eruption that took place in Lanzarote (Canary Islands) between 1730 and 1736, to be used in technologies of biomedicine. This approach was inspired by the strong and extremely stable remanent magnetization of slowly cooled rocks from basaltic lavas containing finely members of the hematite–ilmenite (Fe2O3–FeTiO3) series. Besides, the presence of titanium may promote good biocompatibility and an adequate corrosion resistance, as it does in prosthesis. The green, simple, fast, and cost‐effective synthesis of magnetic nanoparticles was attempted using solar vapor‐phase condensation. This technique allows the preparation of large volumes of nanoparticles presenting a narrow particle size distribution without purification steps. Alternatively, high‐energy ball‐milling of rock powder in the presence of organic surfactants was also studied as a potential method to produce, in a one‐step approach, large quantities of nanostructured particles for biomedical applications. As a proof of concept, we explore these materials as candidates to be used in hyperthermia therapy, which promotes selective necrosis of cancer cells by raising the temperature of the tissue slightly above 43 ºC. Results are correlated to their chemical and structural properties and compared to initial igneous rock characteristics. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:09.710504-05:
      DOI: 10.1002/pssc.201300725
       
  • Towards the large scale production of
           (La1‐zCez)(Fe1‐x‐yMnySix)13Hn products for room
           temperature refrigeration
    • Authors: Charlotte Mayer; Alexandra Dubrez, Michel Pierronnet, Peter Vikner
      Pages: 1059 - 1063
      Abstract: In this paper, we present a novel process based on gas atomization and powder metallurgy techniques to produce reliable and stable (La1‐zCez)(Fe1‐x‐yMnySix)13Hn materials, with 0.08 ≤ x ≤ 0.15, 0 ≤ y ≤ 0.05, 0 ≤ z ≤ 0.3 and 1.5 ≤ n ≤ 3. With this process, shaped pieces ready‐to‐use into refrigeration devices can be produced. Gas atomisation is a rapid solidification technique that prevents the La‐Fe‐Si‐type alloy from forming very large α‐Fe dendrites during cooling, allowing to easily and efficiently heat treat the obtained powder to form the magnetocaloric NaZn13‐type intermetallic. In this process, a batch of 500 kg of alloy was first gas atomized into powder. The powder was then annealed at 1373 K under Ar for one hour to reach around 95% of magnetocaloric phase, and subsequently hydrogenated. Finally, the powder was shaped into composite shaped products containing 91.5 wt.% of powder, by extrusion. This process induces no loss of matter and allows producing non fragile pieces comprising thin portions. Our first results on the stability of partially hydrogenated (La,Ce)(Fe,Mn,Si)13 materials are shown and we discuss on the possible existence of conditions of instability liked to both the composition of the magnetocaloric phase and the level of hydrogenation. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:08.295538-05:
      DOI: 10.1002/pssc.201300650
       
  • Remarkable magnetic properties of amorphous hydrogenated carbon
           nanostructured thin films
    • Authors: Ivan Lukitsa; Galina Nikolaychuk, Oleg Moroz
      Pages: 1064 - 1067
      Abstract: Amorphous hydrogenated carbon thin films with 3d metal nanoparticles were deposited on Si and glass‐ceramic substrates by reactive ion‐plasma magnetron sputtering. Thin films have a high complex permittivity ε * and permeability µ * (ε ′ ≈ 1000–10000, ε″ ≈ 100–1500, μ ′ ≈ 10–70, µ ″ ≈ 0.4–10), what can stipulate by anomalous electromagnetic microwave radiation absorption effect. The magnetic parameters as shape of hysteresis loop, values of coercive force, remanence and saturation magnetization were determined from vibrating‐coil magnetometer measurements. The mechanism of absorption in the material under study is described. Obtained results demonstrate a good promise to use this material for the absorption of electromagnetic microwave radiation. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:10.26583-05:0
      DOI: 10.1002/pssc.201300570
       
  • Investigation of the physical properties of entangled electron spin states
           in a solid
    • Authors: Vladimir N. Petrov; Alexander B. Ustinov, Daria V. Petrova, Andrey A. Grib
      First page: 1068
      Abstract: A concept of experimental study of physical properties of entangled electron spin states (enton quasiparticles) in a solid has been suggested in this paper. In order to conduct such investigations we designed the experimental setup and created spin electron detectors of the next generation. The previous types of detectors didn’t meet all our requirements. The two Mott detectors simultaneously measured spin polarization of electrons during test measurements. The results show that Bell inequalities are satisfied in a traditional measurement mode without temporal pulse coincidence that corresponds to measurement mode of particles not being in the entangled state. The usage of pulse coincidence mode will allow establishing the fact of the Bell’s inequalities violation and will proof the existence of entangled electron spin states in a solid. Further measurements at different pulse durations in the pulse coincidence mode and also measurements at different energies and incidence angles will allow determining the lifetime, energy and dispersion of entangled states in a solid.
      PubDate: 2014-04-08T07:10:26.196651-05:
      DOI: 10.1002/pssc.201300714
       
  • Exchange coupling and magnetic anisotropy for different concentration of
           iron based nanoparticles in aligned carbon nanotube arrays
    • Authors: Serghej L. Prischepa; Alexander L. Danilyuk, Alena L. Prudnikava, Ivan V. Komissarov, Vladimir A. Labunov, Francois Le Normand
      First page: 1074
      Abstract: We present results of study of magnetic properties of nanocomposite formed in situ during the synthesis of aligned carbon nanotube (CNT) arrays. CNTs were grown by the atmospheric pressure floating catalyst chemical vapor deposition method. High temperature pyrolysis of ferrocene/xylene solution injected into the quartz tube at high temperature was carried out. By varying the ferrocene content (CF) in the ferrocene/xylene solution we tuned the concentration, location, size, shape and chemical state of iron based catalytic ferromagnetic nanoparticles. The variation of these parameters was reflected in the magnetic properties of the CNT based nanocomposite. In particular, it is shown, that the main interaction mechanism between ferromagnetic nanoparticles for high CF contents is the exchange coupling, while the magnetic anisotropy dominates at low ferrocene concentration. The role of the orientation of the nanotubes is decisive for the observation of magnetic anisotropy. When the alignment is destroyed, the exchange coupling mechanism starts to dominate also for low CF samples. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-15T04:10:23.749351-05:
      DOI: 10.1002/pssc.201300699
       
  • Competition between FFLO and BCS superconducting states in clean
           asymmetrical ferromagnet‐superconductor structures
    • Authors: Yurii N. Proshin; Marat M. Khusainov, Arthur Minnullin
      First page: 1080
      Abstract: The theory of proximity effect, based on the boundaryvalue problem for the Eilenberger function in view of the in‐plane Fulde‐Ferrell‐Larkin‐Ovchinnikov (FFLO) states, is proposed for thin asymmetrical structures FS, where F is a ferromagnetic metal and S is a BCS superconductor. The dependencies of critical temperature on an exchange field of the F metal, electronic correlations in the S and F metals, and thicknesses of layers F and S are calculated for four‐layered FS systems and FS superlattices. A proposed classification of states includes up to 8 different states which are characterized by phase shifts between superconducting order parameters for neighboring S(F) layers and mutual orientation of magnetizations in adjacent F layers. For asymmetrical FS systems the solitary reentrant superconductivity is predicted. It is shown that the 2D‐FFLO state prevails over the BCS one on the solitary peaks wings. The real candidate for observing predicted phenomena is Gd/La system, for which we found the sign and value of the constant of electronelectron interaction in gadolinium and explain the experimentally observed absence of the suppression of three dimensional superconductivity for symmetrical Gd/La superlattice. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-15T04:10:26.572976-05:
      DOI: 10.1002/pssc.201300730
       
  • The left‐hand behaviour of polymer composites with Fe‐based
           microwires
    • Authors: F. X. Qin; Y. Luo, H. X. Peng, J. Tang, M. Ipatov, V. Zhukova, A. Zhukov, J. Gonzalez
      First page: 1086
      Abstract: In the present paper, we deal with the electromagnetic properties of Fe‐rich microwire polymer meta‐composites prepared by embedding glass‐coated Fe‐based microwires into the E‐glass prepreg matrices in a parallel fashion. The free‐space measurement shows that a transmission window was created by adjusting the wire spacing below 7mm, which indicates that double negative index had been obtained. The correlation between the left‐handed feature with the local dielectric response has been established. The ‘natural' double negative behaviour is attributed to the intrinsic domain structure of Fe‐based ferromagnetic wires. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-10T05:32:10.975101-05:
      DOI: 10.1002/pssc.201300561
       
  • Study of the temperature dependence of ferromagnetic resonance
           measurements in nanostructured arrays
    • Authors: V. Raposo; A. G. Flores, M. Zazo, M. Sánchez, J. I. Iñiguez, C. Redondo, D. Navas
      Pages: 1089 - 1092
      Abstract: Ferromagnetic resonance spectroscopy is a powerful technique to analyse the dynamic properties of nanostructured materials. In order to understand the dynamic phenomena in these samples, nickel and permalloy nanostructured dot and line arrays have been prepared using interference lithography. Temperature dependence of the ferromagnetic resonance measurements have been carried out at a frequency of 9.5 GHz as a function of magnetic field from 85 K to room temperature. Nickel and permalloy based samples present a different temperature dependence of the resonance field, with decreasing and increasing values respectively with higher temperatures. Resonance linewidth in permalloy is nearly constant while nickel arrays present a small decrease with increasing temperature. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:14.100196-05:
      DOI: 10.1002/pssc.201300563
       
  • Wideband ferromagnetic resonance in nanostructured line arrays
    • Authors: V. Raposo; A. G. Flores, M. Zazo, J. I. Iñiguez, J. M. Muñoz, P. Hernández, C. Torres, C. Redondo, D. Navas
      Pages: 1093 - 1096
      Abstract: Dynamic properties of magnetic nanostructures have recently been intensively studied due to their potential application in high density perpendicular recording media or magnetic sensors. Permalloy nanostructured line arrays have been prepared using interference lithography. The film thickness is of 50 nm for different lattice periods. The anisotropy field can be investigated by various techniques. One of these techniques is the ferromagnetic resonance spectroscopy (FMR) due to the fact that the resonance field depends directly on the anisotropy. Ferromagnetic resonance measurements have been carried out at as a function of frequency from 1 to 10 GHz for magnetic fields up to 10 kA/m. The sample was placed in coplanar waveguide with the sample plane parallel to the magnetic field. The frequency dependence of the resonance field can be used to calculate the magnetization saturation and anisotropy field under suitable approximations. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:12.710316-05:
      DOI: 10.1002/pssc.201300564
       
  • Magnetisation and magnetoresistance of Mo/Fe/Co superlattices
    • Authors: S. D. Antipov; G. E. Goryunov, T. P. Kaminskaya, A. A. Kornilov, I. M. Novikov, M. N. Pivkina, V. A. Senina, G. V. Smirnitskaya
      Pages: 1097 - 1101
      Abstract: In this paper, we present experimental studies of the structure, magnetic behavior and magnetoresistance of magnetic superlattices (MSL) [Mo(12Å)Fe(xÅ)Co(21Å)]*100 (x=4÷43). MSLs have been obtained by cathode sputtering with oscillating electrons on the substrate of mica (muscovite). MSLs investigated at room temperature are soft ferromagnets with induced in‐plane magnetic anisotropy. Changes in the spontaneous magnetization Iso and coercive force Hc, depending on the thickness of Co layers, are of oscillatory behavior, which is apparently because of the interference effects of electron waves in the spacers and interfaces. Stepped shape of the measured hysteresis loops for some MSLs, is apparently determined by the vortex behavior of the clusters magnetic moments, located in the sample plane, that is confirmed by measurements carried out on the scanning probe microscope. The observed high values of Iso, normalized to the content of Fe and Co, exceeding Iso(Fe)=1710 Gs may be observed due to increasing values of spin and orbital magnetic moments of Fe and Co in the cluster formations and in the interfaces in the states of low‐dimensional local atomic environment, as well as the possible formation of ferromagnetic order in Mo clusters. Studies of resistance and magnetoresistance (MR) of the samples at temperatures from 10 K to 290 K show semiconducting behavior of resistance and a positive sign of the magnetoresistance. The maximum value of MR for a sample of [Mo (12A) Fe (16A) Co (21A)] x100 was 0.04% for [Mo (12A) Fe (10A) Co (21A)]x100 ‐ 0.5%. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-27T07:10:05.888372-05:
      DOI: 10.1002/pssc.201300696
       
  • Domain wall dynamics in nanocrystalline microwires
    • Authors: Alexandra I. Smarzhevskaya; Waclaw Iwasieczko, Viktor N. Verbetsky, Sergey A. Nikitin
      First page: 1102
      Abstract: The paper presents the investigation of GdNiH3.2 hydride magnetocaloric properties. The isothermal magnetization in the fields up to 5 T and heat capacity data are obtained for GdNiH3.2 and GdNi compounds. The maximum value of magnetic entropy change ΔSM in GdNiH3.2 is extremely large and obtained in much lower temperature range compared to GdNi. It is shown that the hydrogenation does not noticeably affect the value of ΔSM but shifts ΔSM(T) maximum to lower temperatures (∼ 11K). The possibility of GdNiH3.2 application in cryogenic devices is discussed. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:19.821729-05:
      DOI: 10.1002/pssc.201300728
       
  • Ferromagnetism and structural defects in V‐doped titanium dioxide
    • Authors: O. Yildirim; M. Butterling, S. Cornelius, Yu. Mikhailovskiy, A. Novikov, A. Semisalova, A. Orlov, E. Gan'shina, N. Perov, W. Anwand, A. Wagner, K. Potzger, A. B. Granovsky, A. Smekhova
      Pages: 1106 - 1109
      Abstract: We report recent experimental results about influence of negatively charged structural defects on room‐temperature ferromagnetism in V‐doped TiO2‐δ thin films with different electric conductivities. Films were prepared on LaAlO3 (001) substrates by RF magnetron sputtering in reduced argon‐oxygen atmosphere, while the V to Ti metal ratio was fixed at 1 at.%. The ferromagnetic order at room temperature (RT) was confirmed by SQUID magnetometry. Positron annihilation spectroscopy (PAS) was applied to check the presence of open‐volume defects in the TiO2–δ matrix. The relation between ferromagnetic properties and amount of negatively charged defects in the studied films was established. The collection of structural, magnetometry, magnetotransport, magneto‐optic and PAS data hints towards the defect‐induced model of ferromagnetism in 1 at.% V‐doped TiO2–δ thin films. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:08.872837-05:
      DOI: 10.1002/pssc.201300722
       
  • Theoretical prediction of the spin glass behavior in the
           low‐temperature phase of Ni2Mn1.36In0.64 Heusler alloy
    • Authors: Vladimir Sokolovskiy; Vasiliy Buchelnikov, Peter Entel
      First page: 1110
      Abstract: The magnetization behavior in the Ni2Mn1.36In0.64 Heusler compound has been investigated using the 3‐6 states Potts Hamiltonian with real unit cell and magnetic exchange couplings calculated from first principles. The random quenched exchange couplings between magnetic atoms located at different coordination shells have been considered. It is found that the spin‐glass behavior is occurred in low‐temperature range when the long‐range magnetic interactions have been account in the third and more coordination shells. The critical temperature of first magnetic transition from a frustrated spin‐glass‐like phase to ordered ferromagnetic one at heating can be predicted by the Monte Carlo simulations using derived exchange constants. This transition has accompanied with a drop of magnetization. The second magnetic transition from ferromagnetic phase to paramagnetic one has appeared with further increasing of temperature. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:24.092509-05:
      DOI: 10.1002/pssc.201300710
       
  • Thermomagnetic and structural analysis of as‐quenched
           Ni49Co1Mn37Sn13
    • Authors: S. Louidi; J. J. Suñol, T. Bachaga, L. González‐Legarreta, W. O. Rosa, B. Hernando
      Pages: 1116 - 1119
      Abstract: It is known that Co substitution in magnetic shape memory Ni‐Mn‐Sn alloys produces changes in their thermomagnetic behaviour. In this work, the Ni49Co1 Mn37Sn13 alloy was obtained by melt spinning in ribbon shape. The ribbon flakes were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), vibrating sample magnetometry (VSM) and differential scanning calorimetry (DSC). SEM micrographs indicate the formation of textured ribbons with columnar grains growing up perpendicular to the ribbons plane. The crystallographic structure of the sample at room temperature is the Heusler L21. DSC cyclic scans reveal the martensitic transformation on cooling and the reverse austenitic transformation on heating below room temperature. The application of a magnetic field produces a decrease in the transformation temperatures. The small amount of Co addition increases the Curie temperature of austenite. These facts suggest that the structural and magnetic phase transformation temperatures of the ribbons could be tuned to the desired functional temperature by controlling the applied magnetic field as well as the cobalt amount. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:13.890451-05:
      DOI: 10.1002/pssc.201300700
       
  • Giant magneto‐impedance effect in thin Finemet nanocrystalline
           microwires
    • Authors: A. Talaat; M. Ipatov, V. Zhukova, J. M. Blanco, M. Churyukanova, S. Kaloshkin, A. Zhukov
      First page: 1120
      Abstract: We studied giant magneto‐impedance (GMI) effect, magnetic and structural properties of thin Finemet‐type (FeCuNbSiB) glass‐coated microwires fabricated by Taylor‐Ulitovsky technique with different composition and diameters, with the aim to achieve the optimal conditions for improving the final GMI response. We observed that GMI can be tailored either by controlling the microwires microstructure through the thermal annealing, or by controlling the quenching rate velocity during the fabrication processes. Finally, we obtained up to 50% GMI in the as‐prepared samples and up to 100% in annealed microwires. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-10T05:42:04.689402-05:
      DOI: 10.1002/pssc.201300708
       
  • Manipulation of magnetic and magneto‐transport properties of
           amorphous glass‐coated microwires through various annealing
           processes
    • Authors: A. Talaat; M. Ipatov, V. Zhukova, J. M. Blanco, A. Zhukov
      First page: 1125
      Abstract: We studied the influence of two different kind of annealing, conventional annealing and current annealing, on the magnetic and magneto‐transport properties of amorphous Co‐Fe rich glass‐coated microwires with the nominal composition Co69.2Fe4.1B11.8Si13.8C1.1 fabricated by Taylor‐Ulitvosky technique. At a certain annealing conditions we have been able to obtain high domain wall velocity with perfectly rectangular hysteresis loop, high giant magneto‐impedance response (GMI) and almost linear with low hysteretic off‐diagonal GMI response simultaneously in the same sample. Such results could be essential from application's point of view. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-10T05:42:03.637596-05:
      DOI: 10.1002/pssc.201300709
       
  • Hopkinson effect in Co‐rich glass‐coated microwires
    • Authors: V. Zhukova; M. Ipatov, A. Talaat, A. Zhukov
      First page: 1130
      Abstract: We present studies of the temperature dependence of AC susceptibility, χ, and magnetization, M in few Fe‐Cr based microwires. We observed drastic increasing of the χ in vicinity of Curie temperature which we interpreted as the Hopkinson effect. Cr content drastically affects the Curie temperature of studied microwires. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-10T05:42:02.560706-05:
      DOI: 10.1002/pssc.201300715
       
  • The structural, magnetic and magnetocaloric properties of Ba doped La
           manganites
    • Authors: George Tonozlis; George Litsardakis
      Pages: 1133 - 1138
      Abstract: The structural, magnetic and magnetocaloric properties of barium doped lanthanum manganites La1‐xBaxMnO3 with x = 0.1, 0.2 and 0.3 compositions were investigated. The X‐ray powder diffraction results show that all samples crystallize in the rhombohedral R‐3c space group. The substitution of La3+ by the larger Ba+2 ions induces an increase of the unit cell volume when the doping level increases from 10% to 20%. On the contrary a further increase of Ba doping at 30% causes a decrease in the volume of unit cell. All samples exhibit a ferromagnetic to paramagnetic transition. Transition temperature increases from 181 K to 319 K with increasing doping level. Above transition temperature the paramagnetic behavior of the samples is well described by the Curie – Weiss law. Arrott‐Belov plots show that all samples follow the behavior expected for a conventional second order transition. The magnetic entropy change and relative cooling power have been determined. ΔSmaxM observed in the vicinity of transition temperature increases monotonically from 1.51 Jkg–1K–1 for x = 0.1 to 2.61 Jkg–1K–1 for x = 0.3 for a field change of 2 T. The observed temperature dependence of ΔSM is explained reasonably well by the Landau theory of second order phase transition. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-03-31T02:10:07.921909-05:
      DOI: 10.1002/pssc.201300720
       
  • Domain wall dynamics in nanocrystalline microwires
    • Authors: Peter Klein; Rastislav Varga, Manuel Vazquez
      First page: 1139
      Abstract: The domain wall velocity in amorphous microwires approaches very high values up to 20 km/s but dynamics is extremely sensitive to time and temperature. On the other hand, high stability in crystalline materials is paid by very low velocity of the domain wall. One possible solution is using of nanocrystalline material, which are produced by controlled annealing from amorphous precursors. Domain wall velocity reaches up to 1 km/s in nanocrystalline microwires based on FINEMET composition. In different group of nanocrystalline microwires based on HITPERM composition was observed temperature stable and fast domain wall up to 3 km/s. In the present contribution, we present new class of nanocrystalline microwires based on FeNiMoB composition, where domain wall velocity up to 12 km/s was observed. In generally, domain wall velocity increases by annealing in FeNiMoB microwires in contrary to FeCoMoB microwires. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:23.141797-05:
      DOI: 10.1002/pssc.201300707
       
  • Thermodynamic analysis of possible phase states in Ni50Mn35In15 Heusler
           alloy
    • Authors: M.A. Zagrebin; V.D. Buchelnikov, K.I. Kostromitin
      First page: 1144
      Abstract: In this work, a phenomenological Ginzburg‐Landau free‐energy model is developed for investigating structural and magnetic phase transitions in Heusler alloy Ni50Mn35In15. In particular, our model accounts for the inversion of the exchange interaction, which is coupled to the structural parameters of the crystal structure. Equilibrium magnetic states of the model are described by two interacting antiferromagtic sublattices with nonequal sublattice magnetizations, which allows for ferro‐, antiferro‐, and ferri‐magnetic solutions. The analysis of calculated phase stability diagrams shows a thermodynamic path that qualitatively reproduces the experimentally observed phase transitions. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-08T07:10:25.169612-05:
      DOI: 10.1002/pssc.201300713
       
  • The change of crystallite sizes and magnetocaloric effect in rapidly
           quenched dysprosium
    • Authors: A. I. Zvonov; N. Yu. Pankratov, D. Yu. Karpenkov, A. I. Smarzhevskaya, A. Yu. Karpenkov, S. A. Nikitin
      First page: 1149
      Abstract: Synthesis of nanocrystalline and microcrystalline dysprosium was carried out. Temperature and field dependences of magnetocaloric effect were performed by direct method in field up to 1.2 T and temperature range 80‐190 K. It was found that the nanocrystalline state leads to a significant reduction of the magnetic phase transition temperatures and to a small increase of the maximum value of the magnetocaloric effect in dysprosium. It is associated with the large amount of interface atoms in nanocrystalline Dy ribbons with a lower number of the nearest‐neighbor atoms, causing the magnetic phase transition temperature decrease. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
      PubDate: 2014-04-15T04:10:25.702862-05:
      DOI: 10.1002/pssc.201300726
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2014