Authors:Li Zhang, Yongqi Fu, Weixing Yu Abstract: Modern Physics Letters B, Volume 30, Issue 03, 30 January 2016. In this paper, a novel optical absorber that is flexible in size for fabrication and unique properties is studied numerically by aid of finite difference in time domain (FDTD) algorithm. The structure consists of three layers based on the metal–dielectric–metal design scheme. The middle layer is a dielectric in which the electronic and magnetic resonance energy dissipates. The bottom side is a metallic plane and the top layer is a hexagonal prism array. We also investigate the influence of the structure parameters on the absorbance and the absorption wavelength. The results show that a perfect absorber can be designed, and the number of the absorption peaks varies from two to three for the different radius of circumcircle of the hexagonal prism ranging from 280 nm to 400 nm. Meanwhile, position of the first absorption peak is nearly unchanged. This unique feature may be a significant advantage and possesses great potential applications such as biosensing and photovoltaic. Additionally, position and amplitude of the first absorption peak is constant for broad incident angles. The absorption is insensitive to the polarization of the incident beam due to the highly symmetric structure. Citation: Modern Physics Letters B PubDate: 2016-01-28T09:32:59Z DOI: 10.1142/S021798491650010X

Abstract: Modern Physics Letters B, Volume 30, Issue 03, 30 January 2016. The structural, electronic, elastic and phonon properties of the cubic spinels AB2O4 (A = Ge, Si; B = Mg, Zn, Cd) compounds at zero pressure are investigated via density functional theory (DFT) using the Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional. It has been shown that the predicted values of the structural parameters ([math] and [math]), bulk modulus [math], elastic constants [math], shear modulus [math] and [math] ratio are in good agreement with the previously reported results. The phonon dispersion curves of the AB2O4 (A = Ge, Si; B = Mg, Zn, Cd) are calculated for the first time using the direct method. The estimated phonon spectra indicate that GeMg2O4, GeZn2O4, GeCd2O4, SiMg2O4 and SiZn2O4 are dynamically stable in the cubic spinel structure. Citation: Modern Physics Letters B PubDate: 2016-01-28T09:32:54Z DOI: 10.1142/S0217984916500020

Authors:Mariya Iv. Trukhanova Abstract: Modern Physics Letters B, Ahead of Print. In this paper, we develop a quantum hydrodynamics (QHD) method for the research of the quantum evolution of a system of spinning particles. We derived the fundamental equation for charged and neutral spinning particles — the energy evolution equation from the many-particle microscopic Schrödinger equation with a spin–spin and Coulomb modified Hamiltonian. We derive the spin contributions to the energy evolution equation, thermal energy and thermal energy current. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:52:27Z DOI: 10.1142/S0217984916500238

Authors:Sandeep Chettri, D. P. Rai, A. Shankar, M. P. Ghimire, R. Khenata, R. K. Thapa Abstract: Modern Physics Letters B, Ahead of Print. In this paper, the structural, electronic and magnetic properties of Nd-doped rare earth aluminate, La[math]Nd[math]AlO3 ([math] = 0%–100%) is studied using the first-principles full potential linearized augmented plane wave (FP-LAPW) method. The effects of partial Nd substitution for La in LaAlO3 are studied using supercell calculations. The electronic structure analysis indicates La[math]Nd[math]AlO3 to be a probable half metal within the spin polarized generalized gradient approximation (GGA). The direct and indirect band gaps are reported and were analyzed as a function of concentration of Nd doping on LaAlO3. The calculated magnetic moments in La[math]Nd[math]AlO3 were found to arise mainly from the Nd-[math] electrons which manifest the magnetic nature of the system. The significant band gap narrowing with increase in doping concentration may find important applications in optoelectronic devices. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:52:24Z DOI: 10.1142/S0217984916500287

Abstract: Modern Physics Letters B, Ahead of Print. The aim of this paper is to provide a simple and reliable analytical expression for the thermodynamic properties calculated in terms of the Debye model using the binomial coefficient, and examine specific heat capacity of CdTe in the 300–1400 K temperature range. The obtained results have been compared with the corresponding experimental and theoretical results. The calculated results are in good agreement with the other results over the entire temperature range. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:52:23Z DOI: 10.1142/S0217984916500263

Authors:N. H. Abdel-Wahab, Lamia E. Thabet Abstract: Modern Physics Letters B, Ahead of Print. In this paper, some properties through the moving four-level [math]-type atom interacting with a two-mode radiation field are presented. We study this system in the presence of the nonlinearity. The exact solution of this model is given by using the Schrödinger equation when the atom and the field are initially in an excited state and a squeezed state, respectively. We employed the results to perform a careful investigation of the temporal evolution of the cross-correlation function, the momentum increment, the difference mean photon numbers and the normal squeezing. The influence of the Kerr and the cross-Kerr medium parameters on these aspects is examined. It is found that the atom-field properties are affected by the changing of these parameters. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:52:20Z DOI: 10.1142/S0217984916500354

Authors:M. T. Thomaz Abstract: Modern Physics Letters B, Ahead of Print. The geometric phase acquired by the vector states under an adiabatic evolution along a noncyclic path can be calculated correctly in any instantaneous basis of a Hamiltonian that varies in time due to a time-dependent classical field. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:36:12Z DOI: 10.1142/S0217984916500214

Authors:V. D. Lakhno Abstract: Modern Physics Letters B, Ahead of Print. A dependence of phonon interaction on the interelectronic distance is found for a translation-invariant (TI) strong-coupling bipolaron. It is shown that the charge induced by the electrons in a TI-bipolaron state is always greater than that in a bipolaron with spontaneously broken symmetry. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:36:07Z DOI: 10.1142/S0217984916500317

Authors:Rukuan Wu, Yu Shi Abstract: Modern Physics Letters B, Ahead of Print. In this paper, we analytically find the ground states of a mixture of two species of pseudospin-[math] Bose gases with interspecies spin exchange in quite generic parameter regimes. In the most interesting phase, the ground state is strongly entangled between the two species in a very wide parameter regime, and is an entangled Bose-Einstein condensate. The phase diagram and elementary excitations are studied. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:36:06Z DOI: 10.1142/S0217984916501311

Authors:Zhipeng Wang, Miao Li, Dan Wang, Qinghe Chen Abstract: Modern Physics Letters B, Ahead of Print. The introduction of extortion strategy has attracted much attention since it dominates any evolutionary opponent in iterated prisoner’s dilemma games. Despite several studies argue that extortion is difficult to survive under strategy imitation and birth–death updating rules in well-mixed populations, it has recently been proven that a myopic best response rule facilitate the evolution of cooperation and extortion. However, such updating rules require a strong assumption of complete knowledge of all players, which is unlikely to hold in social networks in reality. To solve this problem, we introduce the concept of social influence into the model to limit players’ knowledge within their neighborhood. It turns out that this myopia initiated by social influence prevents players from observing superior strategies and therefore enables cooperators and extortioners to be evolutionarily stable. We also suggest that heterogeneous networks contribute to the evolution of cooperation and extortion under such social influence. Citation: Modern Physics Letters B PubDate: 2016-01-28T02:35:57Z DOI: 10.1142/S0217984916500299

Authors:Leili Motevalizadeh, Boshra Ghanbari Shohany, Majid Ebrahimizadeh Abrishami Abstract: Modern Physics Letters B, Ahead of Print. In this paper, we have investigated the effect of Mn doping on the electrical properties of ZnO thin films. ZnO thin films with different amounts of Mn concentrations (0, 5, 10 and 15 mol.%) were prepared by spray pyrolysis technique. The crystal structure was examined by X-ray diffraction (XRD) analysis. XRD patterns showed that all the samples were crystallized in wurtzite structure while a decrease in crystallinity and switch in preferential orientations were observed in Mn-doped thin films comparing to undoped ZnO. The element composition of all thin films was detected by energy dispersive X-ray (EDX). The surface morphology of the films was investigated using field emission scanning electron microscope (FESEM) and optical properties were studied using UV-vis spectroscopy. UV-vis study revealed that the band gap blueshifts with the increase in Mn content and [math] increases with the increase in Mn concentration. The resistivity and activation energy were measured at room temperature and ranging from 373 K to 573 K. Comparing to undoped ZnO thin film, the resistivity of Mn-doped ZnO films increased because of different parameters such as increasing barrier height energy and reducing the oxygen deficiency. Citation: Modern Physics Letters B PubDate: 2016-01-22T01:35:20Z DOI: 10.1142/S021798491650024X

Authors:V. M. Somsikov Abstract: Modern Physics Letters B, Ahead of Print. In this paper, necessity of creation of mechanics of structured particles is discussed. The way to create this mechanics within the laws of classical mechanics with the use of energy equation is shown. The occurrence of breaking of time symmetry within the mechanics of structured particles is shown, as well as the introduction of concept of entropy in the framework of classical mechanics. The way to create the mechanics of non-equilibrium systems in the thermodynamic approach is shown. It is also shown that the use of hypothesis of holonomic constraints while deriving the canonical Lagrange equation made it impossible to describe irreversible dynamics. The difference between the mechanics of structured particles and the mechanics of material points is discussed. It is also shown that the matter is infinitely divisible according to the laws of classical mechanics. Citation: Modern Physics Letters B PubDate: 2016-01-22T01:35:19Z DOI: 10.1142/S0217984916500184

Authors:Zeshun Chen, Changming Xiao, Zhen Yao Abstract: Modern Physics Letters B, Ahead of Print. Supposing the Ising model system is placed in a temperature field with constant high and low temperatures on both sides, then the system will shift to a non-equilibrium steady state with a certain temperature gradient. With the assistance of local temperature, the steady state of two-dimensional Ising model is studied via the avenue of Monte Carlo simulations in this paper. It is found that the local energy and magnetization are continuous, but there is a sharp decline in the magnetization strength when the temperature falls into the range of 2.2–2.4. The local magnetization [math], when the temperature [math]. It is the indication that the system is in the ferromagnetic state. However, when [math], [math], and then the ferromagnetic state turns into the paramagnetic state. Furthermore, a completely new and special state of Ising model system and the corresponding material is possible if the high and low temperatures of the temperature field are larger and smaller than the critical value of the system, respectively. According to this material, the magnetic driving machine, from which a new energy source can be obtained, is qualitatively discussed at the end of this paper. Citation: Modern Physics Letters B PubDate: 2016-01-22T01:35:18Z DOI: 10.1142/S0217984916500226

Authors:Ghahraman Solookinejad, Mohsen Panahi, Elnaz Ahmadi Sangachin, Seyyed Hossein Asadpour Abstract: Modern Physics Letters B, Ahead of Print. The dispersion behaviors of weak probe light in an InGaN/GaN quantum dot (QD) nanostructure driven by a coherent coupling field is investigated. InGaN/GaN QD nanostructure is designed numerically by solving the Schrödinger–Poisson coupled equations. By specific values of QD radius, an appropriate four-level QD nanostructure which is suitable for interaction by a weak probe light and a coherent coupling field is designed. It is shown that switching from normal to anomalous dispersion can be achieved by the intensity of coupling field. Therefore, fast light propagation in this model can be obtained by reduced absorption. Citation: Modern Physics Letters B PubDate: 2016-01-22T01:35:18Z DOI: 10.1142/S0217984916500202

Authors:Lei Li, Yinhai Wang, Haiju Huang, Hong Li, Hui Zhao Abstract: Modern Physics Letters B, Ahead of Print. Cr[math]-doped zinc gallate (ZnGa2O4) near-infrared (NIR) phosphors were synthesized via a high temperature solid state method. The luminescence properties of the phosphors were studied systematically. A significant spectra overlap between the emission of ZnGa2O4 and the absorption of Cr[math] was observed and 300 nm excitation exhibited the most excellent long-lasting luminescence properties among the three main excitation bands. Luminescence intensity was changed with the ratio of Ga[math]/Cr[math] and the blue host emission of ZnGa2O4 was suppressed when doping Cr[math] into ZnGa2O4. The fluorescence decay curves of blue emission of ZnGa2O4 with different Cr[math] doping concentrations indicated that the lifetime of ZnGa2O4 at 505 nm become shorter with the increase of the Cr[math] concentration. Herein, a possible mechanism of long-lasting luminescence in ZnGa2O4: Cr[math] was proposed that the NIR long-lasting luminescence in ZnGa2O4: Cr[math] comes from the persistent energy transfer from ZnGa2O4 to Cr[math]. Citation: Modern Physics Letters B PubDate: 2016-01-22T01:35:18Z DOI: 10.1142/S0217984916500196

Authors:Hongya Wu, Caihui Wang, Hua Fu, Ji Zhou, Shuzhi Zheng Abstract: Modern Physics Letters B, Ahead of Print. A memristive switching phenomena was investigated in macroscale bulk positive temperature coefficient (PTC) thermosensitive ceramics. (Ba[math]Sr[math])TiO3, which is a well-known PTC thermistor, was taken as an example to analyze the memristive behavior of those macroscale bulk ceramics. Hysteretic current–voltage (I–V) characteristics, which are the features of memristor were obtained. The origin of the effect is attributed to the PTC thermosensitive characteristic of the bulk ceramics, and a switching mechanism driven by competing field-driven heat generation and heat dissipation was proposed. Citation: Modern Physics Letters B PubDate: 2016-01-22T01:35:17Z DOI: 10.1142/S0217984916500251

Authors:Zheng-Hua Fang Abstract: Modern Physics Letters B, Ahead of Print. A modified Rydberg–Vinet equation-of-state (mRV EOS) with an arbitrary nonzero-pressure reference point, as is derived strictly from the related Rydberg potential, has been applied to the mantle and the core. The tests and comparisons demonstrate that mRV EOS is superior to the reciprocal [math]-primed equation [see F. D. Stacey and P. M. Davis, Phys. Earth Planet. Inter. 142 (2004) 137] not only because of its higher fitting accuracy but also because it has fewer fitting parameters and is easier to use. Citation: Modern Physics Letters B PubDate: 2016-01-20T06:56:43Z DOI: 10.1142/S0217984916500159

Authors:Aleksandr A. Vasilchenko, Demid M. Tolkachev Abstract: Modern Physics Letters B, Ahead of Print. The system of Kohn–Sham equations is solved self-consistently for the two-dimensional, spatially separated electrons and holes. We find the series of magic numbers for the total angular momentum of the electrons and holes in a strong magnetic field. The change of the angular momentum of the charge carriers is shown to lead to the persistent current oscillations. Citation: Modern Physics Letters B PubDate: 2016-01-20T06:56:38Z DOI: 10.1142/S0217984916500135

Authors:Igor K. Petrushenko Abstract: Modern Physics Letters B, Ahead of Print. This paper studies the mechanical properties of polyethylene (PE)–Single-walled carbon nanotube (SWCNT) complexes by using density functional theory (DFT). At the PBE/SVP level, the Young’s modulus of the complexes is obtained as a function of PE content. It is established that, with increasing number of PE chains attached to the SWCNTs, the Young’s modulus monotonically decreases. The density of states (DOS) results show that no orbital hybridization exists between the PE chains and nanotubes. The results of this work are of importance for the design of composite materials employing SWCNTs. Citation: Modern Physics Letters B PubDate: 2016-01-20T06:56:34Z DOI: 10.1142/S0217984916500123

Authors:V. Soti, B. Abedi Ravan Abstract: Modern Physics Letters B, Ahead of Print. Electronic transport and switching properties of molecule-based magnetic tunnel junctions are investigated using the first-principles density functional theory and non-equilibrium Green function methods. As a result of being sandwiched between the ferromagnetic electrodes, a spin-polarization is induced in the nonmagnetic organic atoms. Magnitudes of the spin-polarizations in the trans-polyacetylene, cis-polyacetylene, terphenyl and pentacene chains are calculated and it is suggested that among these the pentacene molecules, because of showing a relatively higher magnetization can theoretically be more appropriate for utilization in spintronic devices. Furthermore, electrical switching capabilities of the junctions are studied and the results reveal that the pentacene junction due to having a larger ON/OFF ratio shows a better switching behavior. Finally, magnetoresistive properties are studied and it is shown that applying torsion can be an effective method to enhance and also adjust magnitudes of the magnetoresistances of the junctions. Citation: Modern Physics Letters B PubDate: 2016-01-20T06:56:22Z DOI: 10.1142/S0217984916500172

Authors:Yong-Li Che, Xiao-Long Cao, Jian-Quan Yao Abstract: Modern Physics Letters B, Ahead of Print. The asymmetrical nested metamaterial, composed of two split-ring resonators (SRRs) and two embedded gallium arsenide (GaAs) islands placed in the two SRRs, has been elaborately designed on quartz substrate. Its tunable and switchable resonances at terahertz (THz) frequencies are numerically demonstrated here based on different conductivities of GaAs, which can be transformed from semiconductor to metallic state through appropriate optical excitation. Without photoexcitation, our designed metamaterial has three resonance peaks in the range of monitored frequency range, and they are located at 0.813, 1.269 and 1.722 THz, respectively. As the conductivity of the two GaAs islands increases, different new resonances appear and constantly strengthen. Finally, four new resonant points are generated, at 0.432, 0.948, 1.578 and 1.875 THz, respectively. At the same time, the metamaterial structure is changed from the original nested mode to a new integral mode. Applying reversible changing conductivity of semiconductor to push the conversion of resonance, this asymmetrical nested design provides a new instance in application and development of additional THz devices. Citation: Modern Physics Letters B PubDate: 2016-01-20T06:56:18Z DOI: 10.1142/S0217984916500111

Authors:Lidong Wang, Xiang Wang, Fengchun Lei, Heng Liu Abstract: Modern Physics Letters B, Ahead of Print. It is proved that a nontrivial compact dynamical system with asymptotic average shadowing property (AASP) displays uniformly distributional chaos or distributional chaos in a sequence. Moreover, distributional chaos in a system with AASP can be uniform and dense in the measure center, that is, there is an uncountable uniformly distributionally scrambled set consisting of such points that the orbit closure of every point contains the measure center. As a corollary, the similar results hold for the system with almost specification property. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:28:15Z DOI: 10.1142/S0217984916500019

Authors: Naeemullah, G. Murtaza, R. Khenata, S. Bin Omran Abstract: Modern Physics Letters B, Ahead of Print. For the first time, the electronic and optical properties of the quaternary Be[math]Mg[math]Zn[math]Se alloy have been investigated using first-principles calculations within the framework of density functional theory (DFT). Variations in the direct band gap with the change in [math] and [math] compositions show agreement with the experimental measurements. Evaluation of the dielectric function and refractive index reveals the optical activity in the visible and ultraviolet energy regions. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:28:13Z DOI: 10.1142/S021798491650007X

Authors:Manvir S. Kushwaha Abstract: Modern Physics Letters B, Ahead of Print. Those who measure success with culmination do not seem to be aware that life is a journey not a destination. This spirit is best reflected in the unceasing failures in efforts for solving the problem of controlled thermonuclear fusion for even the simplest pinches for over decades; and the nature keeps us challenging with examples. However, these efforts have permitted researchers the obtention of a dense plasma with a lifetime that, albeit short, is sufficient to study the physics of the pinch effect, to create methods of plasma diagnostics, and to develop a modern theory of plasma processes. Most importantly, they have impregnated the solid state plasmas, particularly the electron–hole plasmas in semiconductors, which do not suffer from the issues related with the confinement and which have demonstrated their potential not only for the fundamental physics but also for the device physics. Here, we report on a two-component, cylindrical, quasi-one-dimensional quantum plasma subjected to a radial confining harmonic potential and an applied magnetic field in the symmetric gauge. It is demonstrated that such a system, as can be realized in semiconducting quantum wires, offers an excellent medium for observing the quantum pinch effect at low temperatures. An exact analytical solution of the problem allows us to make significant observations: Surprisingly, in contrast to the classical pinch effect, the particle density as well as the current density display a determinable maximum before attaining a minimum at the surface of the quantum wire. The effect will persist as long as the equilibrium pair density is sustained. Therefore, the technological promise that emerges is the route to the precise electronic devices that will control the particle beams at the nanoscale. I have no fear to shout out my ignorance and let the Wise correct me, for every instance of such narrows the gulf between them and me. Michael A. Harrington Citation: Modern Physics Letters B PubDate: 2016-01-15T03:28:01Z DOI: 10.1142/S0217984916300027

Authors:Jing Zhou, Hongzhi Shen, Guanlin Feng, Dapeng Xu Abstract: Modern Physics Letters B, Ahead of Print. Fe-doped In2O3 nanotubes were successfully synthesized by electrospinning technique followed by subsequent heat treatment. The as-prepared samples appeared as an apparently open-end one-dimensional (1D) and tubular-like morphology with the diameter of approximately 150 nm and the wall thickness about 20 nm. The diffraction peak of the obtained nanotubes shifts toward bigger angle direction with the increase of the Fe content. Comparing to the In2O3 nanotubes, the Fe-doped In2O3 nanotubes exhibit better sensing characteristics toward ethanol gases, including higher sensing response, lower operating temperature and higher selectivity. Enhanced sensing properties are attributed to 1D hollow nanostructures and the role of doping Fe element. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:28:01Z DOI: 10.1142/S0217984916500044

Authors:M. N. V. Ramesh, K. V. Ramesh Abstract: Modern Physics Letters B, Ahead of Print. Cerium-doped 0.8BaTiO3-0.2Bi[math]K[math]TiO3 with composition 0.8Ba0.2(Bi[math]K[math])Ti[math]Ce[math]O3 where x = 0.01, 0.02, 0.03, 0.04, 0.05, 0.06 lead free ceramics were prepared by conventional solid state reaction method followed by high energy ball milling. X-ray diffraction studies confirm the tetragonal structure at room temperature for all the Ce-doped samples. Lattice parameters and density were increasing with increase of Ce doping. Frequency and temperature dependent dielectric studies were carried out and indicate that the dielectric constant and Curie temperature are decreasing with increasing of Ce doping. All the Ce-doped samples exhibiting diffused and dispersive phase transitions with degree of diffuseness ranging from 1.4 to 2 calculated from the modified Curie–Weiss law. Impedance studies confirms the temperature dependent non-Debye kind of relaxation process in the material. From the Cole–Cole plots measured at high temperatures, reveals that the grain effect in the all Ce-doped samples. Impedance analysis studies also support the X-ray diffraction and dielectric studies that occupation of Ce both at A-site and B-site for small values of Ce doping. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:27:57Z DOI: 10.1142/S0217984916500561

Authors:Lei Liu, Bo Tian, Wen-Rong Sun, Yu-Feng Wang, Yun-Po Wang Abstract: Modern Physics Letters B, Ahead of Print. The transition phenomenon of few-cycle-pulse optical solitons from a pure modified Korteweg–de Vries (mKdV) to a pure sine-Gordon regime can be described by the nonautonomous mKdV–sinh-Gordon equation with time-dependent coefficients. Based on the Bell polynomials, Hirota method and symbolic computation, bilinear forms and soliton solutions for this equation are obtained. Bäcklund transformations (BTs) in both the binary Bell polynomial and bilinear forms are obtained. By virtue of the BTs and Ablowitz–Kaup–Newell–Segur system, Lax pair and infinitely many conservation laws for this equation are derived as well. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:27:56Z DOI: 10.1142/S0217984916500081

Authors:F. Pennini, A. Plastino, M. C. Rocca Abstract: Modern Physics Letters B, Ahead of Print. The basic idea of a microscopic understanding of thermodynamics is to derive its main features from a microscopic probability distribution. In such a vein, we investigate the thermal statistics of quasi-probabilities’s semiclassical analogs in phase space for the important case of quadratic Hamiltonians, focusing attention in the three more important instances, i.e. those of Wigner, [math]- and Husimi distributions. Introduction of an effective temperature permits one to obtain a unified thermodynamic description that encompasses and unifies the three different quasi-probability distributions. This unified description turns out to be classical. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:27:41Z DOI: 10.1142/S0217984916500056

Abstract: Modern Physics Letters B, Ahead of Print. Bound states degenerated in energy (and differing in parity) may form in one-dimensional quantum mechanics if the potential is unbounded from below. We focus on symmetric potential and present quasi-exactly solvable (QES) model based on WKB method. The application of this method is limited on slow-changing potentials. We consider the overlap integral of WKB wave functions [math] and [math] which correspond to energies [math] and [math], and by setting [math], we determine the type of spectrum depending on parameter [math] which arises from this method. For finite value [math], we show that the entire spectrum will consist of degenerated bound states. Citation: Modern Physics Letters B PubDate: 2016-01-15T03:27:38Z DOI: 10.1142/S0217984916500032

Authors:Geoffrey Tse, Dapeng Yu Abstract: Modern Physics Letters B, Ahead of Print. We studied the crystal structure of perovskite BiAlO3 using ab initio density functional theory (DFT) calculations. Using the atomic positions given by the previous literature, we were able to create a lattice structure using visualization software Material Studio. Such sophisticated structure is found in rhombohedral perovskite system with space group with R3c (#161) and lattice parameter of [math], bond angle of [math], while treating the exchange–correlation potential with the local density approximations (LDA) method. The calculations were performed to investigate the electronic, optical, elastic and phonon properties. Citation: Modern Physics Letters B PubDate: 2016-01-05T11:03:00Z DOI: 10.1142/S0217984916500068

Authors:Ze-Jin Yang, Qing-He Gao, Yun-Dong Guo, Zhi-Jun Xu, Ling Tang Abstract: Modern Physics Letters B, Ahead of Print. The structural properties of Mo2Ga2C are simulated by first-principles under pressure. At 40 GPa, the axial compressibilities of [math]- and [math]-axes are 0.9763 and 0.9264, respectively, which are the known largest and smallest values in the [math] compounds. A phase transition at 48 GPa is observed with an abrupt increase of [math]-axis and a rapid decrease of [math]-axis. The elastic properties and phonon imaginary frequencies confirmed the structural transition at 48 GPa, which probably should be the lowest-pressure transition in the [math] ([math], etc.) phases. The anti-expansion of Mo–Mo bond length is responsible for the [math]-axis ultra-incompressibility as well as the structural transition at 48 GPa. Citation: Modern Physics Letters B PubDate: 2015-12-30T05:58:04Z DOI: 10.1142/S0217984916501050

Authors:Gundolf Schenk, Brad Krajina, Andrew Spakowitz, Sebastian Doniach Abstract: Modern Physics Letters B, Ahead of Print. In vivo chromosomal behavior is dictated by the organization of genomic DNA at length scales ranging from nanometers to microns. At these disparate scales, the DNA conformation is influenced by a range of proteins that package, twist and disentangle the DNA double helix, leading to a complex hierarchical structure that remains undetermined. Thus, there is a critical need for methods of structural characterization of DNA that can accommodate complex environmental conditions over biologically relevant length scales. Based on multiscale molecular simulations, we report on the possibility of measuring supercoiling in complex environments using angular correlations of scattered X-rays resulting from X-ray free electron laser (xFEL) experiments. We recently demonstrated the observation of structural detail for solutions of randomly oriented metallic nanoparticles [D. Mendez et al., Philos. Trans. R. Soc. B 360 (2014) 20130315]. Here, we argue, based on simulations, that correlated X-ray scattering (CXS) has the potential for measuring the distribution of DNA folds in complex environments, on the scale of a few persistence lengths. Citation: Modern Physics Letters B PubDate: 2015-12-29T06:21:03Z DOI: 10.1142/S0217984916501177

Authors:Geoffrey Tse, Dapeng Yu Abstract: Modern Physics Letters B, Ahead of Print. In this work, the strain dependence of electronic and optical properties in wurtzite zinc oxide (ZnO) lattice were explored. Ab initio density functional theory (DFT) was used in evaluating the energy bandgap and the dielectric tensor, respectively. The influence on the bandgap due to the shear distortion was so small that the reducing linear trends on uniaxial compressive/tensile strain were reported, in which the evolution of the absorption curve with uniaxial strain agrees well with the experimental results across the bending section. This study provides a set of useful data in analyzing the evolution of the optical adsorption across the bending ZnO nanowire, and gives a systematic explanation to the available experiments from the electronic structure’s perspective. Citation: Modern Physics Letters B PubDate: 2015-12-23T07:07:55Z DOI: 10.1142/S0217984916500482

Authors:E. B. Manoukian Abstract: Modern Physics Letters B, Ahead of Print. This communication is involved in providing, via a modern approach, a direct derivation that, with 100% probability, none of the atomic electrons falls to the center of multi-electron atoms — a problem which has been around historically in the quantum mechanics of atoms since the birth of the former and has, undoubtedly, come across every learner of the subject since then. No need arises for explicit eigenfunctions. Citation: Modern Physics Letters B PubDate: 2015-12-17T07:55:57Z DOI: 10.1142/S0217984916500822

Authors:S. V. Savich, A. V. Samoilov, R. V. Vovk, O. V. Dobrovolskiy, S. N. Kamchatna, Ya. V. Dolgopolova, O. A. Chernovol-Tkachenko Abstract: Modern Physics Letters B, Ahead of Print. The electrical conductivity of hafnium (Hf)-doped [math] ceramics is investigated. Hf doping has been revealed to lead to an increase of the number of effective scattering centers for the normal charge carriers. In a broad temperature range, the excess conductivity of the investigated samples obeys an exponential temperature dependence, while near [math] it is satisfactorily described by the Aslamazov–Larkin model. Meanwhile, Hf doping has been shown to lead to a notable broadening of the temperature range for the manifestation of the pseudogap anomaly in the [math]-plane. Citation: Modern Physics Letters B PubDate: 2015-12-09T09:41:23Z DOI: 10.1142/S0217984916500342