In this work, we employed the elegant tool of Bopp’s shift and standard perturbation theory methods to obtain a new relativistic and nonrelativistic approximate bound state solution of the deformed Klein(cid:21)Gordon and deformed Schr(cid:4)odinger equations using the modi-(cid:28)ed equal vector scalar Manning(cid:21)Rosen plus a class of Yukawa potentials (DVSMCY-Ps, in short) model. Furthermore, we have employed the improved approximation to the centrifugal term for some selected diatomic molecules, such as N 2 , I 2 , HCl, CH, LiH, and CO, in the symmetries of extended quantum mechanics to obtain the approximate solutions. The relativistic shift energy ∆ E totmcy ( n, δ, η, b, A, V 0 , V (cid:48) 0 , Θ , σ, χ, j, l, s, m ) and the perturbative nonrelativistic corrections ∆ E nrmcy ( n, δ, η, b, A, V 0 , V (cid:48) 0 , Θ , σ, χ, j, l, s, m ) appeared as a function of the parameters ( δ, η, b, A, V 0 , V (cid:48) 0 ) , the parameters of noncommutativity (Θ , σ, χ ) , in addition to the atomic quantum numbers ( n, j, l, s, m ) . In both relativistic and nonrelativistic problems, we show that the corrections to the spectrum energy are smaller than the main energy in the ordinary cases of relativistic quantum mechanics and nonrelativistic quantum mechanics. A straightforward limit of our results to ordinary quantum mechanics shows that the present result under DVSMCY-Ps is consistent with what is obtained in the literature. In the new symmetries of noncommutative quantum mechanics, it is not possible to get exact analytical solutions for l = 0 , and l (cid:54) = 0 can only be solved approximately. We have observed that the DKGE under the DVSMCY-Ps model has a physical behavior similar to the Du(cid:30)n(cid:21)Kemmer equation for meson with spin-1, it can describe a dynamic state of a particle with spin-1 in the symmetries of relativistic noncommutative quantume mechanics.
{"title":"New bound-state solutions of the deformed Klein–gordon and Schrödinger equations for arbitrary l-state with the modified equal vector and scalar Manning–Rosen plus a class of Yukawa potentials in RNCQM and NRNCQM symmetries","authors":"A. Maireche","doi":"10.30970/jps.25.4301","DOIUrl":"https://doi.org/10.30970/jps.25.4301","url":null,"abstract":"In this work, we employed the elegant tool of Bopp’s shift and standard perturbation theory methods to obtain a new relativistic and nonrelativistic approximate bound state solution of the deformed Klein(cid:21)Gordon and deformed Schr(cid:4)odinger equations using the modi-(cid:28)ed equal vector scalar Manning(cid:21)Rosen plus a class of Yukawa potentials (DVSMCY-Ps, in short) model. Furthermore, we have employed the improved approximation to the centrifugal term for some selected diatomic molecules, such as N 2 , I 2 , HCl, CH, LiH, and CO, in the symmetries of extended quantum mechanics to obtain the approximate solutions. The relativistic shift energy ∆ E totmcy ( n, δ, η, b, A, V 0 , V (cid:48) 0 , Θ , σ, χ, j, l, s, m ) and the perturbative nonrelativistic corrections ∆ E nrmcy ( n, δ, η, b, A, V 0 , V (cid:48) 0 , Θ , σ, χ, j, l, s, m ) appeared as a function of the parameters ( δ, η, b, A, V 0 , V (cid:48) 0 ) , the parameters of noncommutativity (Θ , σ, χ ) , in addition to the atomic quantum numbers ( n, j, l, s, m ) . In both relativistic and nonrelativistic problems, we show that the corrections to the spectrum energy are smaller than the main energy in the ordinary cases of relativistic quantum mechanics and nonrelativistic quantum mechanics. A straightforward limit of our results to ordinary quantum mechanics shows that the present result under DVSMCY-Ps is consistent with what is obtained in the literature. In the new symmetries of noncommutative quantum mechanics, it is not possible to get exact analytical solutions for l = 0 , and l (cid:54) = 0 can only be solved approximately. We have observed that the DKGE under the DVSMCY-Ps model has a physical behavior similar to the Du(cid:30)n(cid:21)Kemmer equation for meson with spin-1, it can describe a dynamic state of a particle with spin-1 in the symmetries of relativistic noncommutative quantume mechanics.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"171 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79962213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Structure and electronic properties of cspbbr3 perovskite: first principle calculations","authors":"M. Kovalenko, O. Bovgyra, V. Kolomiets","doi":"10.30970/jps.25.4701","DOIUrl":"https://doi.org/10.30970/jps.25.4701","url":null,"abstract":"","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"206 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74462019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Martynyuk-Lototska, I. Yidak, O. Korneyev, A. Ratych, A. Andrushchak
This paper presents the results of ultrasonic measurements in trigonal LiTaO3 crystals. The samples of direct section with faces perpendicular to the main crystallographic axes and X/45 sections of LiTaO3 crystals were manufactured for experimental studies. The velocities of longitudinal and transverse acoustic waves along the three principal crystallographic axes and two additional axes in theYZ plane in trigonal crystals of point group 3m LiTaO3 crystals were measured using the pulse-echo overlap method. In the piezoelectric crystals, elastic and electrical properties are related and the propagation of an acoustic wave is accompanied by the appearance of electric (cid:28)elds, which must be taken into account in the calculations. The relations for the complete determination of all components of the matrices of elastic sti(cid:27)ness and piezoelectric coe(cid:30)cients based on all necessary acoustic wave velocities measured were derived from the Christo(cid:27)el equation for the piezoelectric crystals. Using the obtained ratios, all components of the tensors of piezoelectric coe(cid:30)cients, elastic sti(cid:27)ness constants, as well as all elastic compliances of LiTaO3 crystals are calculated. The obtained results are consistent with the literature data and will be used in further measurements and calculation of the spatial anisotropy of induced (electro-, piezo- and acousto-optical) e(cid:27)ects on the same crystal samples in order to select the most e(cid:27)ective geometry of their possible practical use.Key
{"title":"Determination of all piezoelectric coefficients and elastic stiffness constants in LiTaO3 crystals based on measurements of acoustic wave velocities","authors":"I. Martynyuk-Lototska, I. Yidak, O. Korneyev, A. Ratych, A. Andrushchak","doi":"10.30970/jps.25.4602","DOIUrl":"https://doi.org/10.30970/jps.25.4602","url":null,"abstract":"This paper presents the results of ultrasonic measurements in trigonal LiTaO3 crystals. The samples of direct section with faces perpendicular to the main crystallographic axes and X/45 sections of LiTaO3 crystals were manufactured for experimental studies. The velocities of longitudinal and transverse acoustic waves along the three principal crystallographic axes and two additional axes in theYZ plane in trigonal crystals of point group 3m LiTaO3 crystals were measured using the pulse-echo overlap method. In the piezoelectric crystals, elastic and electrical properties are related and the propagation of an acoustic wave is accompanied by the appearance of electric (cid:28)elds, which must be taken into account in the calculations. The relations for the complete determination of all components of the matrices of elastic sti(cid:27)ness and piezoelectric coe(cid:30)cients based on all necessary acoustic wave velocities measured were derived from the Christo(cid:27)el equation for the piezoelectric crystals. Using the obtained ratios, all components of the tensors of piezoelectric coe(cid:30)cients, elastic sti(cid:27)ness constants, as well as all elastic compliances of LiTaO3 crystals are calculated. The obtained results are consistent with the literature data and will be used in further measurements and calculation of the spatial anisotropy of induced (electro-, piezo- and acousto-optical) e(cid:27)ects on the same crystal samples in order to select the most e(cid:27)ective geometry of their possible practical use.Key","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"23 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89077682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present and analyse the performance of di(cid:27)erent combinations of four higher-order numerical integrators and up to nine interpolation schemes applied to the problem involving the Sun and four Gas-giants (outer planets), namely, Jupiter, Saturn, Uranus, and Neptune. The Hermite interpolation schemes obtained by one, two, and three time-step and interpolants for ODEX2 and ERKN integrators are considered in this paper. The interpolants are a special example of an interpolation scheme, which produce an approximation that is continuous across one step and across the complete interval of integration. The interpolants are quite expensive in comparison with the other interpolation schemes. Therefore, one of the objectives of this paper is to investigate the possibilities of replacing the interpolants of certain integrators by other interpolation schemes, perhaps at a cost of a little bit of accuracy. The experiments are performed to examine the error growth in the positions, velocities, and relative error in energy and angular momentum using di(cid:27)erent combinations of integrators and interpolation schemes over a long interval of integration, as long as 100 million years for the Jovian problem with local error tolerances ranging from 10 − 16 to 10 − 08 .
{"title":"Continuous approximations for long-term numerical simulations of the Solar System","authors":"S. Rehman","doi":"10.30970/jps.25.3901","DOIUrl":"https://doi.org/10.30970/jps.25.3901","url":null,"abstract":"We present and analyse the performance of di(cid:27)erent combinations of four higher-order numerical integrators and up to nine interpolation schemes applied to the problem involving the Sun and four Gas-giants (outer planets), namely, Jupiter, Saturn, Uranus, and Neptune. The Hermite interpolation schemes obtained by one, two, and three time-step and interpolants for ODEX2 and ERKN integrators are considered in this paper. The interpolants are a special example of an interpolation scheme, which produce an approximation that is continuous across one step and across the complete interval of integration. The interpolants are quite expensive in comparison with the other interpolation schemes. Therefore, one of the objectives of this paper is to investigate the possibilities of replacing the interpolants of certain integrators by other interpolation schemes, perhaps at a cost of a little bit of accuracy. The experiments are performed to examine the error growth in the positions, velocities, and relative error in energy and angular momentum using di(cid:27)erent combinations of integrators and interpolation schemes over a long interval of integration, as long as 100 million years for the Jovian problem with local error tolerances ranging from 10 − 16 to 10 − 08 .","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"49 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73604938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We propose a two-sublattice proton ordering model for the quasi-one-dimensional CsH 2 PO 4 ferroelectric with hydrogen bonds, which takes into account contributions to the energy of the proton subsystem that are linear in the lattice strains ε 1 , ε 2 , ε 3 , and ε 5 . The model also takes into account the dependence of the e(cid:27)ective dipole moments of pseudospins on the order parameters, which enables us to coordinate the values of the e(cid:27)ective dipole moments in the paraelectric and ferroelectric phases. Within this model in the two-particle cluster approximation for the short-range interactions and in the mean (cid:28)eld approximation for the long-range interactions, the behavior of spontaneous polarization, longitudinal dielectric permittivity, piezoelectric and elastic characteristics, and molar heat capacity under the in(cid:29)uence of uniaxial and hydrostatic pressure and a longitudinal electric (cid:28)eld
{"title":"Influence of uniaxial and hydrostatic pressures and a longitudinal electric field on the thermodynamic characteristics of the quasi-one-dimensional ferroelectric CsH2PO4","authors":"A. Vdovych, R. Levitskii, I. R. Zachek, A. Moina","doi":"10.30970/jps.25.3702","DOIUrl":"https://doi.org/10.30970/jps.25.3702","url":null,"abstract":"We propose a two-sublattice proton ordering model for the quasi-one-dimensional CsH 2 PO 4 ferroelectric with hydrogen bonds, which takes into account contributions to the energy of the proton subsystem that are linear in the lattice strains ε 1 , ε 2 , ε 3 , and ε 5 . The model also takes into account the dependence of the e(cid:27)ective dipole moments of pseudospins on the order parameters, which enables us to coordinate the values of the e(cid:27)ective dipole moments in the paraelectric and ferroelectric phases. Within this model in the two-particle cluster approximation for the short-range interactions and in the mean (cid:28)eld approximation for the long-range interactions, the behavior of spontaneous polarization, longitudinal dielectric permittivity, piezoelectric and elastic characteristics, and molar heat capacity under the in(cid:29)uence of uniaxial and hydrostatic pressure and a longitudinal electric (cid:28)eld","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"10 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81935130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. V. Masleyeva, O. Bogdan, I. Brytavskyi, D. V. Tarasevich, V. V. Shugarova
{"title":"The influence of sulphide surface modification regimes on the mechanism of currents in p-n junctions based on GaAs","authors":"N. V. Masleyeva, O. Bogdan, I. Brytavskyi, D. V. Tarasevich, V. V. Shugarova","doi":"10.30970/jps.25.3705","DOIUrl":"https://doi.org/10.30970/jps.25.3705","url":null,"abstract":"","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"93 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73617518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Moskvin, S. Skurativskyi, O. Gromovyi, W. Sadowski
The Cahn(cid:21)Hilliard model concepts are extended to describe the spinodal decomposition of Ga x In 1 − x P y As 1 − y solid solutions grown on the InP substrate. The energy of elastic deformation of the thin layer of a solid solution was calculated on the assumption of its coherent conjugation with the massive InP substrate. The excess energy of component mixing in the solid phase was modeled in accordance with the simple solution model, when the simultaneous substitution of components in the metal and metalloid sub lattices of the sphalerite structure is incorporated. The system of di(cid:27)erential equations describing vari-ations of the composition of a semiconductor solid solution after its spinodal decomposition was solved numerically under various thermodynamic conditions. The temperature-concentration intervals in which the oscillations of the supersaturated metastable state of the solid phase may take place were found by analyzing the phase portrait of the resulting system of di(cid:27)erential equations. We obtained the thermodynamic synthesis conditions ensuring the appearance of the microoscillations of the solid solution composition. It was shown that the development of intensive oscillations (composition modulation e(cid:27)ect in material) is caused by the mutual transition of all excess thermodynamic energy of mixing of an unstable solid phase into the energy of elastic stresses of the coherently conjugated layers of decaying material (energy resonance). The shape of the component concentration pro(cid:28)les in the obtained oscillatory process di(cid:27)ers si-gni(cid:28)cantly from the shape corresponding to harmonic oscillations. One reason for this is the complex dependence of the model’s parameters of the distribution on the material’s composition. Another reason is that the solutions found are in close proximity to the resonance, which is characterized by a signi(cid:28)cant increase in the oscillation amplitude and, as a consequence, the manifestation of nonlinear properties of the system. The results obtained clearly illustrate the formation of concentration domains during the spinodal decomposition of the multicomponent semiconductor solid phase. The results of the parameter calculation for the oscillatory process were compared with the data on the modulation composition e(cid:27)ect, which is experimentally observed during the production of elastically strained Ga x In 1 − x P y As 1 − y heterostructures. The interval of thermodynamic parameters of the growing system which ensures the development of the composition modulation e(cid:27)ect in Ga x In 1 − x P y As 1 − y solid solutions was considered in detail.
将Cahn(cid:21)Hilliard模型概念扩展到描述生长在InP衬底上的Ga x In 1−x P y As 1−y固溶体的独立分解。在假定固溶薄层与大量InP衬底相干共轭的前提下，计算了固溶薄层的弹性变形能。考虑闪锌矿结构的金属亚晶格和类金属亚晶格中组分的同时取代，根据简单溶液模型对组分在固相中混合的多余能量进行了建模。在不同的热力学条件下，对描述半导体固溶体经旋量分解后组成变化的di(cid:27)代方程组进行了数值求解。通过分析所得到的di(cid:27)递推方程组的相画像，找到了固相过饱和亚稳态可能发生振荡的温度-浓度区间。我们得到了保证固溶体组成微振荡出现的热力学合成条件。结果表明，材料中强振荡(成分调制e(cid:27)等)的发展是由不稳定固相混合的所有多余热力学能量相互转换为衰变材料的相干共轭层的弹性应力能量(能量共振)引起的。在得到的振荡过程中，组分浓度pro(cid:28)与si-gni(cid:28)的形状与谐波振荡对应的形状完全不同。造成这种情况的一个原因是模型的分布参数对材料组成的复杂依赖。另一个原因是，所找到的解与共振非常接近，其特征是振荡幅度不能显著增加(cid:28)，从而表现出系统的非线性特性。所得结果清楚地说明了多组分半导体固相在旋多分解过程中浓度域的形成。将振荡过程的参数计算结果与实验中观测到的调制成分e(cid:27)等数据进行了比较，这些数据是在生产弹性应变的Ga x In 1−x P y As 1−y异质结构过程中得到的。详细考虑了在Ga x in 1−x P y As 1−y固溶体中保证组分调制e(cid:27)ect发展的生长系统热力学参数区间。
{"title":"The composition modulation effect in GaInPAs solid solutions as a manifestation of energy resonance after material's spinodal decomposition","authors":"P. Moskvin, S. Skurativskyi, O. Gromovyi, W. Sadowski","doi":"10.30970/JPS.25.1601","DOIUrl":"https://doi.org/10.30970/JPS.25.1601","url":null,"abstract":"The Cahn(cid:21)Hilliard model concepts are extended to describe the spinodal decomposition of Ga x In 1 − x P y As 1 − y solid solutions grown on the InP substrate. The energy of elastic deformation of the thin layer of a solid solution was calculated on the assumption of its coherent conjugation with the massive InP substrate. The excess energy of component mixing in the solid phase was modeled in accordance with the simple solution model, when the simultaneous substitution of components in the metal and metalloid sub lattices of the sphalerite structure is incorporated. The system of di(cid:27)erential equations describing vari-ations of the composition of a semiconductor solid solution after its spinodal decomposition was solved numerically under various thermodynamic conditions. The temperature-concentration intervals in which the oscillations of the supersaturated metastable state of the solid phase may take place were found by analyzing the phase portrait of the resulting system of di(cid:27)erential equations. We obtained the thermodynamic synthesis conditions ensuring the appearance of the microoscillations of the solid solution composition. It was shown that the development of intensive oscillations (composition modulation e(cid:27)ect in material) is caused by the mutual transition of all excess thermodynamic energy of mixing of an unstable solid phase into the energy of elastic stresses of the coherently conjugated layers of decaying material (energy resonance). The shape of the component concentration pro(cid:28)les in the obtained oscillatory process di(cid:27)ers si-gni(cid:28)cantly from the shape corresponding to harmonic oscillations. One reason for this is the complex dependence of the model’s parameters of the distribution on the material’s composition. Another reason is that the solutions found are in close proximity to the resonance, which is characterized by a signi(cid:28)cant increase in the oscillation amplitude and, as a consequence, the manifestation of nonlinear properties of the system. The results obtained clearly illustrate the formation of concentration domains during the spinodal decomposition of the multicomponent semiconductor solid phase. The results of the parameter calculation for the oscillatory process were compared with the data on the modulation composition e(cid:27)ect, which is experimentally observed during the production of elastically strained Ga x In 1 − x P y As 1 − y heterostructures. The interval of thermodynamic parameters of the growing system which ensures the development of the composition modulation e(cid:27)ect in Ga x In 1 − x P y As 1 − y solid solutions was considered in detail.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"41 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74208995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Rudysh, A. Kashuba, P. Shchepanskyi, R. Petrus, V. Stadnyk, M. Piasecki
Ternary semiconductor materials with a chalcopyrite structure belonging to the I(cid:21)III(cid:21)VI 2 group (where I = Ag, Cu; III = Al, Ga, In; VI = S, Se, Te) attract considerable attention due to interesting physical properties. The structural, electronic and optical properties of these crystals make them promising materials for a number of applications in nonlinear optics devices, detectors, photodiodes, solar cells, etc. In this work, the theoretical (cid:28)rst-principle calculations of the structural, vibrational and dielectric properties of an AgGaS 2 crystal with a chalcopyrite structure are performed. We report the results of the calculations of the phonon band structure ω ( q ) , total and partial density of phonon states N ( ω ) , infrared spectra and Raman spectra, the Born e(cid:27)ective charge tensor for each atom, and dielectric constants (for ω = 0 and ω → 0 ) using the theory of perturbation of the density functional. Theoretical-group analysis of vibrational modes is carried out and the classi(cid:28)cation of vibrations in the phonon spectra of the investigated compound is performed. The results of the phonons calculations showed the stability of the crystal structure of the studied compound. It follows from the calculations of the phonon spectrum that there is a signi(cid:28)cant anisotropy of low-frequency acoustic branches of vibrations. There is also a presence of low-frequency optical branches that interact with acoustic ones. It was found that the density of states can be divided into three parts (cid:22) low-frequency, medium-frequency and high-frequency regions, which are formed by the oscillations of Ag, Ga and S atoms, respectively. The calculated and identi(cid:28)ed frequencies of vibrations modes in the center of the Brillouin zone ( Γ point) showed good agreement with the available experimental data on IR and Raman spectra and theoretical data obtained using the Phonon program. A symmetric classi(cid:28)cation of vibrational modes for a crystal using group theory is performed. Estimation of the Born e(cid:27)ective charge tensor and dielectric constants in an AgGaS 2 crystal indicates their signi(cid:28)cant anisotropy.
{"title":"Calculation of the vibrational spectra of AgGaS2 crystal with chalcopyrite structure","authors":"M. Rudysh, A. Kashuba, P. Shchepanskyi, R. Petrus, V. Stadnyk, M. Piasecki","doi":"10.30970/jps.25.3704","DOIUrl":"https://doi.org/10.30970/jps.25.3704","url":null,"abstract":"Ternary semiconductor materials with a chalcopyrite structure belonging to the I(cid:21)III(cid:21)VI 2 group (where I = Ag, Cu; III = Al, Ga, In; VI = S, Se, Te) attract considerable attention due to interesting physical properties. The structural, electronic and optical properties of these crystals make them promising materials for a number of applications in nonlinear optics devices, detectors, photodiodes, solar cells, etc. In this work, the theoretical (cid:28)rst-principle calculations of the structural, vibrational and dielectric properties of an AgGaS 2 crystal with a chalcopyrite structure are performed. We report the results of the calculations of the phonon band structure ω ( q ) , total and partial density of phonon states N ( ω ) , infrared spectra and Raman spectra, the Born e(cid:27)ective charge tensor for each atom, and dielectric constants (for ω = 0 and ω → 0 ) using the theory of perturbation of the density functional. Theoretical-group analysis of vibrational modes is carried out and the classi(cid:28)cation of vibrations in the phonon spectra of the investigated compound is performed. The results of the phonons calculations showed the stability of the crystal structure of the studied compound. It follows from the calculations of the phonon spectrum that there is a signi(cid:28)cant anisotropy of low-frequency acoustic branches of vibrations. There is also a presence of low-frequency optical branches that interact with acoustic ones. It was found that the density of states can be divided into three parts (cid:22) low-frequency, medium-frequency and high-frequency regions, which are formed by the oscillations of Ag, Ga and S atoms, respectively. The calculated and identi(cid:28)ed frequencies of vibrations modes in the center of the Brillouin zone ( Γ point) showed good agreement with the available experimental data on IR and Raman spectra and theoretical data obtained using the Phonon program. A symmetric classi(cid:28)cation of vibrational modes for a crystal using group theory is performed. Estimation of the Born e(cid:27)ective charge tensor and dielectric constants in an AgGaS 2 crystal indicates their signi(cid:28)cant anisotropy.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"479 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86088650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"State diagrams of one-dimensional ion conductors with the two minima local anharmonic potential for ions","authors":"R. Stetsiv, O. Farenyuk","doi":"10.30970/JPS.25.2702","DOIUrl":"https://doi.org/10.30970/JPS.25.2702","url":null,"abstract":"","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"67 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74121172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：