Deformation Potential Approach to the Calculation of Mobilities of Carriers and Conductivity of trans-Polymonocyanoacetylene

The deformation potential theory for one-dimensional organic polymer is studied. This approximation is then used to calculate the mobilities of carriers and the conductivity of trans-polymonocyanoacetylene (PMCA). The results of calculations are in fairly good agreement with experimental data.

Reinvestigation of potential deformation during a heavy rainfall event in North China

In this study,the physical meaning and generation mechanism of potential deformation(PD)are reinvestigated.A main trait of PD is that it contains deformation,which is an important factor to precipitation but not well applied in precipitation diagnosis.This paper shows PD shares similar features to deformation,but contains much more physical information than deformation.It can be understood as a type of deformation of a thermodynamic-coupled vector(u*,v*).For convenient application,squared PD(SPD)is used instead for analysis.By deriving the tendency equation of SPD,it is found that whether SPD is produced or reduced in the atmosphere is associated with the angle between the dilatation axes of PD and geostrophic PD.When the angle is less thanπ2,SPD is generated.The diagnostic results during a heavy rainfall event in North China on 20 July 2016 show that the process of rapid increase in precipitation can be well revealed by SPD.The distribution of SPD becomes more organized and concentrated with increasing precipitation intensity.A diagnostic analysis of the SPD tendency equation shows that concentrated SPD is associated with the generation of SPD in the boundary layer followed by upward transport of the SPD.The concentration of SPD indicates a confluence of precipitation-favorable factors—namely,vertical wind shear and moist baroclinity,which can enhance vertical motions and thus cause an increase in precipitation.These diagnostic results further verify PD as a useful physical parameter for heavy precipitation diagnosis.

Correlation between mechano-electronic features and scattering rates using deformation potential theory

This research paper provides valuable insight into the electronic,mechanical and transport properties of the Sr_(2)RuO_(2)F_(2)compound.The study shows that the Sr_(2)RuO_(4)compound exhibits a metallic ground state and that the energy gap widens with oxygen substitution with fluorine.The concept of absolute deformation potential and its correlation with band energies and strains is explained using deformation potential theory.The paper also examines the mechanical features of Sr_(2)RuO_(2)F_(2)using the Voigt-Reuss-Hill approximation method and analyzes its elastic constants,bulk modulus and shear modulus,indicating flexibility and suitability for optoelectronic applications.The role of acoustic phonons in scattering rates and carrier mobility in Sr_(2)RuO_(2)F_(2)and its potential for phonon-mediated superconductivity is investigated.The intrinsic resistivity of electrons and holes under strain and its potential impact on superconductivity and electrical resistivity are also discussed.The insight provided by this study contributes to the current understanding of Sr_(2)RuO_(2)F_(2),and its potential applications.

Diameter-dependent ultra-high thermoelectric performance of ZnO nanowires

Zinc oxide(ZnO)shows great potential in electronics,but its large intrinsic thermal conductivity limits its thermoelectric applications.In this work,we explore the significant carrier transport capacity and diameter-dependent thermoelectric characteristics of wurtzite-ZnO(0001)nanowires based on first-principles and molecular dynamics simulations.Under the synergistic effect of band degeneracy and weak phonon-electron scattering,P-type(ZnO)_(73) nanowires achieve an ultrahigh power factor above 1500μW·cm^(-1)·K^(-2)over a wide temperature range.The lattice thermal conductivity and carrier transport properties of ZnO nanowires exhibit a strong diameter size dependence.When the ZnO nanowire diameter exceeds 12.72A,the carrier transport properties increase significantly,while the thermal conductivity shows a slight increase with the diameter size,resulting in a ZT value of up to 6.4 at 700 K for P-type(ZnO)_(73).For the first time,the size effect is also illustrated by introducing two geometrical configurations of the ZnO nanowires.This work theoretically depicts the size optimization strategy for the thermoelectric conversion of ZnO nanowires.

Feinberg-Horodecki Exact Momentum States of Improved Deformed Exponential-Type Potential

We obtain the quantized momentum eigenvalues, Pn, and the momentum eigenstates for the space-like Schrodinger equation, the Feinberg-Horodecki equation, with the improved deformed exponential-type potential which is constructed by temporal counterpart of the spatial form of these potentials. We also plot the variations of the improved deformed exponential-type potential with its momentum eigenvalues for few quantized states against the screening parameter.

Systematic Calculations of α-Decay Half-Lives Using Microscopic Deformed Potentials

A new version of the generalized density-dependent cluster model （GDDCM） is developed to describe an α particle tunneling through a deformed potential barrier. The microscopic deformed potential is numerically constructed in the double-folding model using the multipole ex- pansion method. The decay width of an α-cluster state is evaluated using the integral of the quasi-bound state wave function, the scattering state wave function, and the difference of poten- tials. We perform a systematic calculation of α-decay half-lives for favored transitions in even-even nuclei ranging from Z=52 to Z=104. The calculated half-lives are in good agreement with the experimental values. The relation between nuclear deformations and α-decay half-lives is also discussed in details.

Wave packet dynamics of nonlinear Gazeau–Klauder coherent states of a position-dependent mass system in a Coulomb-like potential

AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scaled down by the quantum number and the nonlinearity coefficient. We study the basic properties of these states, which are found to be undefined on the whole complex plane, and some details of their revival structure are discussed.

Piezoelectric and deformation potential effects of straindependent luminescence in semiconductor quantum well structures

The mechanism of strain-dependent luminescence is important for the rational design of pressure-sensing devices. The interband momentum-matrix element is the key quantity for understanding luminescent phenomena. We analytically solved an infinite quantum well （IQW） model with strain, in the framework of the 6 × 6 k.p Hamiltonian for the valence states, to directly assess the interplay between the spin-orbit coupling and the strain-induced deformation potential for the interband momentum-matrix element. We numerically addressed problems of both the infinite and IQWs with piezoelectric fields to elucidate the effects of the piezoelectric potential and the deformation potential on the straindependent luminescence. The experimentally measured photoluminescence variation as a function of pressure can be qualitatively explained by the theoretical results.

Study on Valence Band Offsets atStrained Heterojunctions

A method, which can predict the valence band offsets at strained layer heterojunctions under different strain situations only by calculating band structures and deformation parameters of the bulk materials, is suggested. The applicability of this method is verified by calculation of the valence band offsets at strained layer heterojuntions ,such as InP/InAs, InP/GaP, GaAs/InAs, GaP/GaAs and AlAs/InAs with various strain conditions.

Simplified Method of Valence Band Offset Calculation at Strained Layer Heterojunction

The average bond energy method is popularized and applied to study band offsets at strained layer heterojunctions. By careful examination of hydrostatic and uniaxial strain actions on the band offset parameter Emv,it is found that the average band offset parameter Emv,av=Em-Ev, av remains basically unchanged under different strain conditions. Therefore, provided the band offset parameter before strain Emv,0 of bulk material is calculated, and the experiment values of deformation potential b and spin-orbit （SO） splitting energy △0 are quoted, the Emv at strained layer can be obtained by a simple and convenient algebraic calculation. Thus the valence band offset △Ev at strained layer heterojunction can also be predicted conveniently. This simplified calculation method is characterized by decreased calculation amount and increased conviction due to use as many as possible the experiment values.

Thermal Expansion of Solids

The work covers a novel approach to the description of the phenomenon of thermal expansion of solids. The reason for undertaking the scientific quest is presented to follow with the analysis of existing knowledge on the characteristics of phenomenon of thermal expansion of bodies being in the state of aggregation. A critical approach to the existing law of the linear thermal expansion is given. The paper presents an adequate approach to this considered phenomenon. The description provides parametric and functional characteristics of this phenomenon. The relationships of the coefficients of linear expansion on temperature for particular interstate zones, as well as the initial coefficients related to these zones, are presented. In the summary a synthesis of all actions and considerations with the directions to the adequate knowledge with advantage on the subjected phenomenon has been performed. It regards also to the latest thermal characteristics of solids, referred to the phase transformations. All they are realized by dilatometric studies together with determination of curves of thermal expansions of solids.

Current Reversals of an Underdamped Brownian Particle in an Asymmetric Deformable Potential

Transport of an underdamped Brownian particle in a one-dimensional asymmetric deformable potential is investigated in the presence of both an ac force and a static force,respectively.From numerical simulations,we obtain the current average velocity.The current reversals and the absolute negative mobility are presented.The increasing of the deformation of the potential can cause the absolute negative mobility to be suppressed and even disappear.When the static force is small,the increase of the potential deformation suppresses the absolute negative mobility.When the force is large,the absolute negative mobility disappears.In particular,when the potential deformation is equal to0.015,the two current reversals present with the increasing of the force.Remarkably,when the potential deformation is small,there are three current reversals with the increasing of the friction coefficient and the average velocity presents a oscillation behavior.