Indian Journal of Physics最新文献

{"title":"Role of anharmonicity binding energy on the transition dynamics of GaAs quantum dot in presence of noise","authors":"Swarnab Datta,&nbsp;Bhaskar Bhakti,&nbsp;Manas Ghosh","doi":"10.1007/s12648-023-02901-x","DOIUrl":"10.1007/s12648-023-02901-x","url":null,"abstract":"<div><p>Present enquiry thoroughly explores the <i>time-average excitation rate</i> (<i>TAER</i>) of <i>GaAs quantum dot</i> (<i>QD</i>) pursuing the change in the <i>anharmonicity binding energy</i> (<i>ABE</i>) of the system and under the supervision of <i>Gaussian white noise</i> (<i>GWN</i>). The promotion of the ground state electronic density occurs due to various kinds of time-varying fluctuations viz. <i>simple sinusoidal field</i> (<i>SSF</i>), <i>time-dependent confinement potential</i> (<i>TDCP</i>), <i>time-dependent magnetic field</i> (<i>TDMF</i>), <i>polychromatic radiation field</i> (<i>PRF</i>), <i>pulsed field</i> (<i>PF</i>), <i>chirped pulsed field</i> (<i>CPF</i>), <i>time-dependent anharmonicity constant</i> (<i>TDAC</i>) and <i>time-dependent noise strength</i> (<i>TDNS</i>). GWN couples with the QD by <i>additive</i> and <i>multiplicative</i> modes. The work analyzes the consequence of joint influence of a few parameters that guides the attributes of the TAER diagrams. These parameters involve <i>ABE</i>, inclusion of GWN in a given pathway, the parity of the anharmonic potential and the type of the time-dependent perturbations. The TAER curves are enriched with steadfast rise, steadfast diminish, maximization (relevant to generation of large <i>nonlinear optical properties</i>), minimization and saturation (suggesting <i>dynamic freezing</i>). The findings highlight the utility of different kinds of time-dependent fluctuations to fine-tune the TAER among the <i>GaAs</i> QD eigenfunctions when the <i>ABE</i> of QD carries out a continual change.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 4","pages":"1247 - 1258"},"PeriodicalIF":1.6,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74164490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving entanglement and inhabiting depolarization of two-mode entangled coherent-squeezed states","authors":"A. Dehghani","doi":"10.1007/s12648-023-02889-4","DOIUrl":"10.1007/s12648-023-02889-4","url":null,"abstract":"<div><p>Here we apply a two-mode Binomial-like superposition of the photon-number operators (GSP operation) on each mode of the entangled coherent-squeezed states (ECSS), which are called GSP-ECSS from here on. In order to gain more insight into the effectiveness of this operation, and for comparison with the case already discussed as the photon-added ECSS, we present a general analysis of non-classical properties such as the photon statistics, degree of polarization, and the entanglement of the GSP-ECSS. We show that a particular choice of the parameters of the GSP operation enables us to prevent these states from depolarization as well as disentanglement. In other words, the GSP operation can be considered a reliable approach in the framework of quantum information theory which leads to the improvement of the non-classicality of the quantum states, especially their entanglement.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 3","pages":"821 - 827"},"PeriodicalIF":1.6,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86710804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of atomic ensemble position on the dynamics of cold atoms in an optical cavity: normal-mode splitting","authors":"Neha Aggarwal,&nbsp;Sonam Mahajan,&nbsp;Neha Batra,&nbsp;Aranya B. Bhattacherjee","doi":"10.1007/s12648-023-02914-6","DOIUrl":"10.1007/s12648-023-02914-6","url":null,"abstract":"<div><p>We consider the dynamics of cold atoms coupled to the light field via radiation pressure within a Fabry-Perot cavity. We observe the effects of changing the effective positioning of the atomic ensemble on the effective mechanical frequency and the damping rate of cold atoms. We further study the displacement spectrum of the atomic oscillator and analyze the occurrence of normal mode splitting into two modes. We mainly analyze how the position of the ensemble acts as an additional tool in significantly altering the atomic and cavity field interaction strength. The present scheme enables further studies of coherently controlling the dynamics of the cold atoms.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 4","pages":"1211 - 1216"},"PeriodicalIF":1.6,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89504593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The standardization expressions of the neutron-induced nuclear reactions","authors":"P. F. Ji,&nbsp;Y. L. Song,&nbsp;F. Q. Zhou,&nbsp;Y. J. Hao,&nbsp;X. P. Zhang,&nbsp;S. Q. Yuan","doi":"10.1007/s12648-023-02890-x","DOIUrl":"10.1007/s12648-023-02890-x","url":null,"abstract":"<div><p>The neutron-induced nuclear reaction data play an important role in the studies of the nuclear structure, the nuclear reaction mechanism and the nuclear energy applications. Particularly, the cross section data of the neutron-induced nuclear reactions are an indispensable component in the studies of the nuclear technology such as fusion devices, fission power plants, and accelerators. In the actual cross section measurements of the neutron-induced nuclear reactions with natural samples containing many stable isotopes, many nuclear reactions will take place at the same time and the mutual interference of various nuclear reactions is difficult to avoid. In this case, the standardization expressions of the neutron-induced nuclear reactions are particularly important. The expressions of the neutron-induced nuclear reactions in the relevant literatures are various and confusing, which is bad not only for the academic exchanges and the construction of nuclear reaction databases, but also for the basic research and the related application research of the nuclear physics. Some problems related to the expressions on the neutron-induced nuclear reactions were carefully combed and discussed, and the suggestions on the standardization expressions of the neutron-induced nuclear reactions (which were divided into the single nuclear reaction and the multiple nuclear reaction producing the same daughter nucleus. And the former was further divided into the daughter nucleus with metastable state and the daughter nucleus without metastable state, while the latter into the nuclear reaction that directly produces the same daughter nucleus and the nuclear reaction that directly and indirectly produces the same daughter nucleus) were given. The work is useful for the academic exchanges, the construction of the nuclear reaction databases, the basic researches and the related application researches of the nuclear physics.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 2","pages":"717 - 724"},"PeriodicalIF":1.6,"publicationDate":"2023-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88828179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electronic, elastic, and thermodynamic properties of Cd0.75TM0.25S (TM = Os or Ir) alloys with the TB-mBJ approach and hybrid density functional (HSE06)","authors":"M. Boudjelal,&nbsp;M. Batouche,&nbsp;T. Seddik,&nbsp;K. Bouhadjer,&nbsp;S. Bentata,&nbsp;R. Khenata,&nbsp;A. Belfedal,&nbsp;N. Badi,&nbsp;S. Bin-Omran","doi":"10.1007/s12648-023-02875-w","DOIUrl":"10.1007/s12648-023-02875-w","url":null,"abstract":"<div><p>The electronic structure, elastic moduli, as well as thermodynamic features of the ferromagnetic Cd_0.75TM_0.25S (TM = Os or Ir) compounds in the zinc-blende phase were investigated by employing the “generalized gradient approximations” parametrized by Wu and Cohen combined with the “modified Becke-Johnson (TB-mBJ)” as well as the hybrid functional (HSE06). The predicted total magnetic moments for the transition metals Os and Ir are 4.0 μB and 3.0 μB with TB-mBJ and are 2.0 μB and 3.0 μB using the hybrid functional (HSE06) for compounds Cd_0.75Os_0.25S and Cd_0.75Ir_0.25S, respectively. The generation of magnetic moments and spin-polarization in these alloys is directly linked to the contribution coming from TM-5d states. The ferromagnetic properties of these alloys were predicted by the computed exchange constants Besides, the increase in the porosity paramete<span>(N_{0alpha })</span> and <span>(N_{0beta })</span>. The Total and partial densities of states (TDOS/PDOS) and the behavior of electronic band structures (EBS) were also calculated to describe the ferromagnetic semiconducting and half-metallic (HM) characteristics with TB-mBJ and the hybrid functional (HSE06). According to the findings, Cd_0.75Os_0.25S is a half-metallic ferromagnetic (HM) material with a full polarization spin distribution of electrons at the Fermi energy level, exhibiting metallicity for the majority spin and a semiconducting nature for the minority spin. In contrast, Cd_0.75Ir_0.25S is a ferromagnetic half-semiconductor (HSC) with two distinct gaps depending on the up and down spin configurations. Calculations of the elastic constants, Young and shear moduli reveal that the compound Cd_0.75TM_0.25S (TM = Os or Ir) is mechanically stable, has a high degree of anisotropy, and is naturally ductile. Furthermore, the “quasi-harmonic Debye model” was performed to examine the thermodynamic properties of the studied compounds, including the thermal capacity, entropy and Debye temperature.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 3","pages":"921 - 935"},"PeriodicalIF":1.6,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75623539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study of the melting process of spherical phase change material with variable thermal conductivity","authors":"Tanvi Singla,&nbsp;B. Kumar,&nbsp;Sapna Sharma","doi":"10.1007/s12648-023-02886-7","DOIUrl":"10.1007/s12648-023-02886-7","url":null,"abstract":"<div><p>This paper addresses the melting of phase change solid sphere, which motivates researchers to develop new thermal energy storage (TES) systems techniques. Phase change materials can store or release large amounts of heat in short intervals of time, thus improving the thermal performance of cooling and heating systems in buildings and regulate the temperature of PV systems, batteries and other electronic components. We have considered a convective spherical Stefan problem with thermal conductivity as a function of time and temperature. The heat balance integral method (HBIM) is used to find the problem’s solution numerically. The temperature profile is approximated by using n degree polynomial. The influence of governing parameters on the location of melting front and temperature profile is discussed thoroughly. The parameters depict that transition from solid to liquid phase becomes fast for higher values of Stefan number while the transition rate slows down for larger values of Peclet number. The melting rate increases from 20% to 80% when Stefan number rises from 0.1 to 1.0 at a particular time. Moreover, a comparative study of the proposed model with some existing models is being done. It is observed that moving melting front for the assumed problem undergoes a fast melting process.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 4","pages":"1355 - 1363"},"PeriodicalIF":1.6,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73189210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrically tunable optical properties of one-dimensional photonic crystal containing nanocomposite structurally chiral material","authors":"Simin Shirin,&nbsp;Amir Madani,&nbsp;Samad Roshan Entezar","doi":"10.1007/s12648-023-02888-5","DOIUrl":"10.1007/s12648-023-02888-5","url":null,"abstract":"<div><p>In the present paper, the reflection and transmission properties of a one-dimensional photonic crystal made of alternate layers of isotropic dielectric medium and electro-optic nanocomposite structurally chiral medium (NSCM) are investigated. The electro-optic NSCM is a nanocomposite medium consisting structurally chiral material (SCM) where the silver nanoparticles are randomly dispersed inside it. The numerical results show three kinds of photonic bandgap in this structure, including traditional Bragg gap, circular Bragg gap and plasmonic absorption bandgap, which is due to the plasmonic resonance and absorption of the silver nanoparticles. The effect of the external low-frequency electric field is investigated on the reflection and transmission spectra of the structure. It is shown that the impact of the applied voltage depends on the value of the tilt angle and the maximum changes are experienced for the case of <span>(chi = 90^circ)</span>. Also, the results show that the width of the traditional and circular Bragg gaps is sensitive to the applied voltage; however, the variation of the circular Bragg gap is more noticeable.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 4","pages":"1463 - 1470"},"PeriodicalIF":1.6,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75877879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The behavior of weak shock waves under the influence of weak gravitational field","authors":"Dhanpal Singh,&nbsp;Ekta Jain,&nbsp;S. D. Ram","doi":"10.1007/s12648-023-02864-z","DOIUrl":"10.1007/s12648-023-02864-z","url":null,"abstract":"<div><p>This paper employs an analytical approach to achieve a precise solution and physical application for the unsteady one-dimensional adiabatic flow of weak shock waves with generalized geometries in a non-viscous perfect fluid under the influence of a weak gravitational field. In the disturbed region, the density is considered to have a functional relationship with distance, meaning that a relative change in distance from the source of disturbance causes a corresponding change in density. Finally, the problem’s solution comes in the shape of distance and time power. The current technique handles this scenario in a natural way, and the approximations produce results that are reasonably accurate.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 3","pages":"797 - 802"},"PeriodicalIF":1.6,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86225901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetic treatment of lower hybrid waves excitation in a magnetized dusty plasma by electron beam","authors":"Anshu,&nbsp;Suresh C. Sharma,&nbsp;Jyotsna Sharma","doi":"10.1007/s12648-023-02865-y","DOIUrl":"10.1007/s12648-023-02865-y","url":null,"abstract":"<div><p>The theoretical modelling of electrostatic lower hybrid waves (LHWs) is investigated using a kinetic treatment involving an electron beam. This electron beam propagates through a magnetized dusty plasma cylinder that consists of dust grains, electrons, and positively charged potassium ions (<i>K</i> +). The excitation of LHWs via Cerenkov interaction using an analytical model is driven to instability. In order to explain how a population of charged dust particles affects the LHWs growth rate in a plasma that has been stimulated by an electron beam, a dispersion relation has been developed. The dust grain particles impact has been discussed on the growth rate of LHWs, and it was discovered that with the rise in relative density of dust grains, the growth rate of LHWs augments. Also, the growth rate of the unstable mode decreases with the frequency of the lower hybrid wave. Furthermore, the critical drift velocity for excitation of the mode is derived, and it was observed that it decreases as the relative density of negatively charged dust grains augments. The current study's findings align with the existing experimental observations.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 3","pages":"1147 - 1153"},"PeriodicalIF":1.6,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78672107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On electromagnetic curves and geometric phase associated with frontals in de-Sitter 2-space","authors":"Bahar Doğan Yazıcı,&nbsp;Sıddıka Özkaldı Karakuş","doi":"10.1007/s12648-023-02876-9","DOIUrl":"10.1007/s12648-023-02876-9","url":null,"abstract":"<div><p>In this work, we introduce a Berry phase model which is very important in physics relative to the frontals in de-Sitter 2-space. With this approach, we examine the relationship between a singular curve and Fermi–Walker’s law and Berry’s phase law in de-Sitter 2-space. We give the Rytov curves by using an orthonormal frame of spacelike frontals and timelike frontals with Fermi–Walker parallelism. We express parametric representations of Rytov curves associated with a singular optical fiber. We examine electromagnetic curves associated with orthonormal vectors of spacelike frontals and timelike frontals in de-Sitter 2-space. Hence, we express the magnetic field equations, Lorentz force equations and magnetic trajectory equations along a singular optical fiber. Finally, we give examples that support the theories both physically and geometrically.</p></div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"98 3","pages":"1021 - 1030"},"PeriodicalIF":1.6,"publicationDate":"2023-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76320862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}