Indian Journal of Physics最新文献_第8页

Self-focusing of a linearly polarized laser beam in a semi-bounded thermomagnetic relativistic quantum plasma 半有界热磁相对论量子等离子体中线偏振激光束的自聚焦

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-06-02 DOI: 10.1007/s12648-026-04014-7

Majid Amirzadeh, Davood Raoufi

{"title":"Self-focusing of a linearly polarized laser beam in a semi-bounded thermomagnetic relativistic quantum plasma","authors":"Majid Amirzadeh, Davood Raoufi","doi":"10.1007/s12648-026-04014-7","DOIUrl":"10.1007/s12648-026-04014-7","url":null,"abstract":"<div>This study explores the self-focusing behavior of a linearly polarized laser beam as it propagates through a semi-bounded weakly relativistic magnetized thermal quantum plasma. The dynamics of the plasma are described using the quantum hydrodynamic (QHD) model, which accounts for quantum effects such as electron degeneracy pressure, originating from Fermi statistics and the Bohm potential, which arises due to quantum tunneling, along with relativistic modifications. An external magnetic field is applied in the direction of laser propagation. When the laser enters the plasma, the presence of the magnetic field causes its linear polarization to split it to right and left circularly polarized components. This change in polarization, significantly affects the dynamics of the plasma particles. To derive the nonlinear wave equation for the circularly polarized laser beam in quantum weakly relativistic magnetized thermal plasma, a perturbative method is employed. The equation result clearly reveals how quantum and relativistic effects influence the plasma’s dispersion relation and its effective refractive index. Finally, a set of coupled equations is obtained for the self-focusing behavior of the right- and left-handed modes that emerge from the initially linearly polarized laser beam. The analysis shows that quantum effects, such as the quantum potential and Fermi pressure, alter the beam’s behavior and influence its self-focusing. Increasing the magnetic field strength enhances the self-focusing, while increasing the laser frequency tends to weaken it. Moreover, an increase in plasma density and laser intensity further enhances the self-focusing of the beam.</div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"100 8","pages":"3457 - 3468"},"PeriodicalIF":1.7,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148433720","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}

引用次数: 0

Signatures of the breakup threshold anomaly in 9Be + 144Sm elastic scattering: a multi-potential analysis 9Be + 144Sm弹性散射破裂阈值异常的多势分析

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-06-01 DOI: 10.1007/s12648-026-04081-w

D. M. Janseitov, D. S. Valiolda, S. K. Sakhiyev, B. Mauyey, Awad A. Ibraheem, Sh. Hamada

引用次数: 0

Intrinsic defect assisted luminescence and magnetic properties of Eu3+ and Gd3+ ions doped NiO nanoparticles Eu3+和Gd3+离子掺杂NiO纳米颗粒的内在缺陷辅助发光和磁性能

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-06-01 DOI: 10.1007/s12648-026-04074-9

M. Naseem Siddique, Vikas kumar, P. Tripathi, Sachin Kumar

{"title":"Intrinsic defect assisted luminescence and magnetic properties of Eu3+ and Gd3+ ions doped NiO nanoparticles","authors":"M. Naseem Siddique, Vikas kumar, P. Tripathi, Sachin Kumar","doi":"10.1007/s12648-026-04074-9","DOIUrl":"10.1007/s12648-026-04074-9","url":null,"abstract":"<div>In the present work, we experimentally discussed the surface vacancy defect related luminescence and magnetic properties for pure and RE3+ ions (Eu3+, Gd3+) doped NiO nanoparticles synthesized by sol–gel method. In this regard, structural and morphological analyses were carried out by XRD, SEM and TEM measurements to analyze the crystallite size and morphology of prepared nanoparticles, respectively. The compositional analysis was also carried out by the FTIR spectroscopy. The UV visible absorption spectra of all the prepared materials reveal a strong absorption edge in between 300–400 nm due to the exciton transition and the optical bandgap energy (Eg) increases with the incorporations of Eu3+ and Gd3+ ions. On the other hand, the deconvoluted PL spectra for all the prepared samples demonstrate a remarkable blue emission under the excitation wavelength 270 nm. The blue emission was attributed to the deep level emission due to intrinsic defect (doubly ionized Ni vacancy) states in prepared doped NiO nanoparticles as supported by CIE1961 chromaticity diagram. In addition, the color purity for the blue emission was also calculated with the help of CIE coordinates and observed a higher value for the doped samples over the pure NiO sample. In continuation, magnetic measurement shows a weak room temperature ferromagnetism in all the prepared nanoparticles. The apperance of weak ferromagnetism due to the presence of induced Ni vacancies on the surface of nanoparticles as confirmed by the PL analysis. Consequently, by the incorporation of RE3+ ions (Eu3+ and Gd3+) in NiO lattice, one can tune the luminescence and magnetization induced by intrinsic defects which can be utilized in the applications of optoelectronic and spintronic devices.</div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"100 10","pages":"4093 - 4105"},"PeriodicalIF":1.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148909510","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}

引用次数: 0

First principle insights, Electronic, P-Dos, optical properties, and Elastic Tensor calculation of Ba2KOsO6 Triple Perovskite Ba2KOsO6三重钙钛矿的第一性原理见解，电子，p - do，光学性质和弹性张量计算

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-29 DOI: 10.1007/s12648-026-04079-4

Alkesh H. Barot, Zalak Shah, Piyush J. Patel, Mitesh B. Solanki

{"title":"First principle insights, Electronic, P-Dos, optical properties, and Elastic Tensor calculation of Ba2KOsO6 Triple Perovskite","authors":"Alkesh H. Barot, Zalak Shah, Piyush J. Patel, Mitesh B. Solanki","doi":"10.1007/s12648-026-04079-4","DOIUrl":"10.1007/s12648-026-04079-4","url":null,"abstract":"<div>The triple perovskite Ba2KOsO6 has been investigated by first-principles density functional theory within the Perdew–Burke–Ernzerhof generalised gradient approximation. The compound crystallises in the cubic Fm3m space group, featuring ordered Ba, K, and Os cations within corner-sharing OsO6 octahedra. Spin-polarised electronic band-structure calculations along the high-symmetry path W–L–Γ–X–W–K reveal an indirect band gap of 2.5 eV in the spin-up channel and 2.8 eV in the spin-down channel, confirming a robust semiconducting ground state with no states crossing the Fermi level. The projected density of states shows strong hybridisation between Os 5d and O 2p orbitals in the valence band, while the conduction band is dominated by Os 5d states; the spin asymmetry yields a net magnetic moment localised on the Os6+ sites, consistent with ferrimagnetic ordering. Optical properties derived from the complex dielectric function demonstrate pronounced absorption in the visible-to-ultraviolet range, moderate refractive index, and low reflectivity, indicating suitability for optoelectronic and magneto-optical devices. Elastic-tensor calculations confirm mechanical stability (all Cij > 0), ductility (B/G > 1.25), and elastic anisotropy, with bulk modulus 26.33 GPa and Young’s modulus 34.94 GPa. These results establish Ba2KOsO6 as a promising Os-based triple perovskite for spintronic, optical, and mechanically robust applications.</div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"100 10","pages":"4161 - 4170"},"PeriodicalIF":1.7,"publicationDate":"2026-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148909707","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}

引用次数: 0

Halogen-tunable Rb2NaIrX6 double perovskites: a computational study of optoelectronic, photocatalytic, and thermoelectric performance 卤素可调Rb2NaIrX6双钙钛矿：光电、光催化和热电性能的计算研究

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-24 DOI: 10.1007/s12648-026-04076-7

Si Mohammed Djamel Eddine, Debidatta Behera, Mohammed Batouche, Mohamed El Amine El Goutni, Tabeti Abdelkader, Taieb Seddik, Dalila Hammoutène

{"title":"Halogen-tunable Rb2NaIrX6 double perovskites: a computational study of optoelectronic, photocatalytic, and thermoelectric performance","authors":"Si Mohammed Djamel Eddine, Debidatta Behera, Mohammed Batouche, Mohamed El Amine El Goutni, Tabeti Abdelkader, Taieb Seddik, Dalila Hammoutène","doi":"10.1007/s12648-026-04076-7","DOIUrl":"10.1007/s12648-026-04076-7","url":null,"abstract":"<div>We performed a comprehensive first-principles investigation of the cubic double perovskites Rb2NaIrBr6 and Rb2NaIrI6 using density functional theory. Structural optimization confirms that both compounds crystallize in the stable Fm-3m phase with corner-sharing [IrX6] octahedra, while Br → I substitution expands the lattice and reduces the bulk modulus, indicating higher compressibility for the iodide. Electronic calculations within WC-GGA and TB-mBJ show that both materials are direct band gap semiconductors at the Γ point, with tunable band gaps ranging from ~ 0.87 to 1.09 eV (WC-GGA) and from ~ 1.64 to 2.11 eV (TB-mBJ). Optical spectra reveal high dielectric constants and strong visible–UV absorption, with enhanced optical response for Rb2NaIrI6. Elastic constants satisfy the Born–Huang stability criteria, and both compounds are predicted to be brittle and elastically anisotropic. Thermoelectric transport calculations based on Boltzmann theory indicate p-type behavior with large Seebeck coefficients and increasing ZT at elevated temperature, reaching ~ 0.78 for Rb2NaIrBr6 and ~ 0.85 for Rb2NaIrI6 at 900 K. These results highlight Ir-based halide double perovskites as mechanically stable, optically active, and thermoelectrically promising lead-free materials for multifunctional energy and optoelectronic applications.</div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"100 10","pages":"4125 - 4142"},"PeriodicalIF":1.7,"publicationDate":"2026-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148909550","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}

引用次数: 0

Development of a projectile charge state analyzer for MeV energy ion–atom/molecule collision experiments 用于MeV能量离子-原子/分子碰撞实验的弹丸电荷状态分析仪的研制

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-22 DOI: 10.1007/s12648-026-04060-1

Sandeep Bajrangi Bari, Sahan Raghava Sykam, Ranojit Das, Rohit Tyagi, A. H. Kelkar

引用次数: 0

Density functional theory evaluation of the strain-induced optoelectronic and thermoelectric attributes of monolayer XO2 (X = Pd, Pt) 单层XO2 （X = Pd, Pt）薄膜应变致光电和热电特性的密度泛函理论评价

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-22 DOI: 10.1007/s12648-026-04070-z

Kamal Kumar, Aparna Dixit, Mumtaz Manzoor, Abhishek Kumar Mishra, Ramesh Sharma, Yedluri Anil Kumar

{"title":"Density functional theory evaluation of the strain-induced optoelectronic and thermoelectric attributes of monolayer XO2 (X = Pd, Pt)","authors":"Kamal Kumar, Aparna Dixit, Mumtaz Manzoor, Abhishek Kumar Mishra, Ramesh Sharma, Yedluri Anil Kumar","doi":"10.1007/s12648-026-04070-z","DOIUrl":"10.1007/s12648-026-04070-z","url":null,"abstract":"<div>Two-dimensional (2D) metal oxide (MO) monolayers (MLs) have attracted considerable research attention due to their promising thermoelectric (TE) and optoelectronic (OE) characteristics. In this study, density functional theory (DFT) calculations are performed to investigate pristine 2D XO2 (X = Pd, Pt) MLs and their behaviour under uniform biaxial tensile and compressive strains ranging from − 10 to + 10%. Their TE performance is evaluated using the BoltzTraP code based on Boltzmann transport theory. Our findings reveal that both MLs exhibit a direct-band-gap (Eg) semiconducting nature in their pristine state. Notably, the semiconducting behaviour is preserved across the entire strain range, with no closure of Eg observed. However, at − 10% compressive strain, the nature of Eg for both MLs transitions from direct to indirect. Furthermore, the TE properties of both MLs exhibit strong strain dependence. For PdO2, the power factor (PF) increases significantly from 709.9 in the pristine state to 5.52 × 106 under 10% tensile strain. Similarly, PtO2 shows enhanced TE performance, with a PF of 4070.59 at 1% tensile strain compared to 1430.55 in the unstrained condition. The optical analysis further reveals strong light-matter interaction, with both MLs exhibiting a high refractive index n(ω) in the low-energy region (~ 2–3 eV). These results demonstrate that strain engineering can effectively tune and enhance the optical spectra and TE response of XO2 MLs.</div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"100 9","pages":"3641 - 3654"},"PeriodicalIF":1.7,"publicationDate":"2026-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148752124","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}

引用次数: 0

First principle study of electronic, optical properties and Raman spectroscopy of alkali earth metals doped ceria 碱土金属掺杂二氧化铈的电子、光学性质及拉曼光谱第一性原理研究

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-21 DOI: 10.1007/s12648-026-04058-9

Lemessa Asefa Eressa

{"title":"First principle study of electronic, optical properties and Raman spectroscopy of alkali earth metals doped ceria","authors":"Lemessa Asefa Eressa","doi":"10.1007/s12648-026-04058-9","DOIUrl":"10.1007/s12648-026-04058-9","url":null,"abstract":"<div>First-principle calculations were used to investigate the electronic and optical properties of ceria doped with alkali earth metals, following the Perdew-Burke-Ernzerhof (PBE-GGA) scheme. The doping of ceria with alkali earth metals leads to the formation of an indirect band gap which is attributed to the differences in symmetry points between ceria and the dopants. Optical properties, including the real and imaginary dielectric constant, refractive index, extinction coefficient, reflectivity, and absorption coefficient, were computed using thermo_pw software connected to Quantum Espresso. Compared to pure ceria, doped ceria with alkali earth metals exhibited the highest absorption peaks in the visible light energy range from 1.63 to 3.26 eV. This suggests that alkali earth metal doping enhances ceria’s optical absorption. The Raman spectroscopy study was employed to investigate the structural and spectral response of alkali earth metals doped ceria. The Raman spectroscopy analysis of alkali earth metals doped ceria revealed three peaks: the main peak characteristic of the ceria structure (~ 445–452 cm-1), a defect-induced peak (~ 600–630 cm-1), and a secondary structural mode peak (~ 690–705 cm-1), respectively. The doping of alkali earth metals in ceria modifies its electronic, optical, and Raman spectroscopic properties, making it promising for technological applications.</div>","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":"100 10","pages":"4417 - 4424"},"PeriodicalIF":1.7,"publicationDate":"2026-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12648-026-04058-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148909809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study of the Sharma-Mittal holographic reconstructed dark energy models in the (mathcal {F(Q)}) gravity (mathcal {F(Q)})重力中Sharma-Mittal全息重建暗能量模型的研究

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-19 DOI: 10.1007/s12648-026-04047-y

Myra Nisar, Kanwal Nazir

引用次数: 0

Structural, Mössbauer and magnetic properties of Fe60Al40 nanostructured powders synthesized by high-energy mechanical alloying 高能机械合金化制备Fe60Al40纳米粉体的结构、Mössbauer及磁性能

IF 1.7 4区物理与天体物理

Indian Journal of Physics Pub Date : 2026-05-19 DOI: 10.1007/s12648-026-04062-z

M. Hemmous, A. Guittoum, T. Kacel

引用次数: 0