Indian Journal of Physics最新文献_第3页

Sharma-mittal HDE model in anisotropic universe 各向异性宇宙中的 Sharma-mittal HDE 模型

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-09-01 DOI: 10.1007/s12648-024-03374-2

T. Vinutha, K. Niharika, K. Venkata Vasavi

{"title":"Sharma-mittal HDE model in anisotropic universe","authors":"T. Vinutha, K. Niharika, K. Venkata Vasavi","doi":"10.1007/s12648-024-03374-2","DOIUrl":"https://doi.org/10.1007/s12648-024-03374-2","url":null,"abstract":"The current study explores the Sharma-Mittal holographic dark energy (SMHDE) by considering Bianchi-(VI_0) space-time in Saez-Ballester’s theory. The model’s exact solutions are procured by assuming the relationship between metric potentials. The Hubble horizon is regarded as the Infrared cutoff to examine our model’s cosmic effects. The physical behavior of the model is investigated by considering two fluids- SMHDE and pressureless matter. The behavior of the cosmological parameters, such as the deceleration parameter, EoS parameter, (rho _{de}), (rho _m), statefinder, and (v_s^2), was evaluated with the help of their plots with respect to redshift(z) to study the nature of the universe. The figure of the deceleration parameter predicts that the present model transits from the deceleration to the acceleration period of the universe. The EoS parameter for this model agrees with the recent astrophysical observations, which lie within the range of quintessence region. In the case of statefinder and (v_s^2), the model shows Chaplygin gas and stability throughout the region. The perturbation technique is used to evaluate the stability of the resulting model. Finally, the results of the current model support the existence of an accelerating universe with the present observational data.","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215855","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

Effects of magnetic field on the Rashba spin–orbit interaction in an asymmetry quantum well 磁场对不对称量子阱中拉什巴自旋轨道相互作用的影响

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-31 DOI: 10.1007/s12648-024-03376-0

Shan Shuang, Lan Hong, Jun Ge, Da.-Quan Liu

引用次数: 0

First principles insight into magneto-electronic and optical properties of half-metallic-ferromagnetism binary GaN compound for spintronic applications 对用于自旋电子应用的半金属铁磁二元氮化镓化合物的磁电子和光学特性的第一原理认识

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-30 DOI: 10.1007/s12648-024-03240-1

Nazia Iram, Aparna Dixit, Bandar Ali Al-Asbahi, Ramesh Sharma, Javed Ahmad, Zubair Ahmad, Imad Barsoum

引用次数: 0

Valley polarization of electrons in a graphene under modulations of the electrostatic potential barrier and the magnetic field 静电势垒和磁场调制下石墨烯中电子的谷极化

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-29 DOI: 10.1007/s12648-024-03390-2

R. S. Luo, J. D. Lu, X. Y. Li, H. Wang

引用次数: 0

Lie symmetry approach for shock wave propagation in a self-gravitating non-ideal gas under the influence of monochromatic radiation and magnetic field in rotating medium 旋转介质中单色辐射和磁场影响下自重力非理想气体中冲击波传播的李对称方法

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-29 DOI: 10.1007/s12648-024-03352-8

G. Nath, P. Upadhyay

{"title":"Lie symmetry approach for shock wave propagation in a self-gravitating non-ideal gas under the influence of monochromatic radiation and magnetic field in rotating medium","authors":"G. Nath, P. Upadhyay","doi":"10.1007/s12648-024-03352-8","DOIUrl":"https://doi.org/10.1007/s12648-024-03352-8","url":null,"abstract":"The propagation of cylindrical shock wave influenced by monochromatic radiation and magnetic field in a self-gravitating non-ideal gas for a rotating medium has been investigated by using the Lie symmetry method. Ahead of the shock front, the ambient density of the medium is taken as constant, while the magnetic field, azimuthal and axial velocities vary over time. By using the Lie symmetry approach, the optimal system for the governing equations, the similarity variable and transformations are obtained. By the use of derived similarity transformations, the governing equations change into a system of ODEs (ordinary differential equations). The software package “Mathematica” has been utilized to solve the system of ODEs numerically and to generate the graphs for the flow variables distribution. In this article, the strength of the shock wave and variations in the flow variables of the flow field region behind the shock front, which are influenced by the strength of the ambient magnetic field, gravitational parameter, non-idealness parameter, adiabatic exponent, and rotational parameter, are examined in detail. It has been demonstrated that the magnetic field, non-idealness parameter, adiabatic exponent, and rotational parameter have decaying effect on the shock wave. In contrast, the gravitational parameter has reversed impact on the shock strength.","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215856","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

Structural and optical properties of Cr3+ doped SiO2 nanophosphor 掺杂 Cr3+ 的二氧化硅纳米磷的结构和光学特性

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-29 DOI: 10.1007/s12648-024-03392-0

L. F. Koao, R. A. Phokojoe, R. G. Moji, S. V. Motloung, T. E. Motaung, H. C. Swart

{"title":"Structural and optical properties of Cr3+ doped SiO2 nanophosphor","authors":"L. F. Koao, R. A. Phokojoe, R. G. Moji, S. V. Motloung, T. E. Motaung, H. C. Swart","doi":"10.1007/s12648-024-03392-0","DOIUrl":"https://doi.org/10.1007/s12648-024-03392-0","url":null,"abstract":"SiO2:x% Cr3+ (0 ≤ x ≤ 8) nanopowder samples were synthesized using the sol-gel method. The effect of Cr3+ doping concentration on the SiO2 nanoparticles was studied for possible application in light-emitting diodes (LEDs). Structure and optical properties of undoped and Cr3+ doped SiO2 nanoparticles were investigated in detail. X-ray diffraction (XRD) results confirmed the amorphous phase for undoped SiO2 (A-SiO2) nanopowder. However, above 0.8% Cr3+ there were secondary peaks due rhombohedral structure of chromium (III) oxide (R-Cr2O3). Ultraviolet-visible spectroscopy (UV-Vis) spectra showed a reflectance peak at around 320 nm for the undoped sample. The results showed that when the concentration of Cr3+ is increased there was an emergence of reflectance peaks at around 309, 419, and 553 nm which were attributed to the presence of the Cr2O3 lattices. The photoluminescence (PL) results revealed that with an increase in the amount of Cr3+, the maximum peaks in blue and near red emerge at around 2.82 and 1.89 eV, respectively. Those peaks may be due to defects within both SiO2 and R-Cr2O3. The emission peaks of undoped and Cr3+ doped SiO2 match well with the Uv-vis results. The international illumination colour chromaticity showed that above 0.8% Cr3+ the colour shifts from yellow to blue with an increase in Cr3+ concentration. The investigation indicated that Cr3+ doped SiO2 have a potential application in blue and yellow LED chips for lighting.","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215871","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

Study of multiple degrees of freedom entanglement in optical fiber 光纤中多自由度纠缠的研究

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-28 DOI: 10.1007/s12648-024-03378-y

Huimin Zhang, Chaoying Zhao

引用次数: 0

Domain-wall dark pulse generation with polyacrylonitrile as saturable absorber 以聚丙烯腈为可饱和吸收体的域壁暗脉冲发生器

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-28 DOI: 10.1007/s12648-024-03384-0

Xiaoyou Song, Abdulkadir Mukhtar Diblawe, Zian Cheak Tiu, Sameer Salam, Fatimah Ibrahim, Sulaiman Wadi Harun

引用次数: 0

Anisotropic cosmological models in f(T) theory of gravity with mixture of fluids 具有流体混合物的 f（T）引力理论中的各向异性宇宙学模型

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-27 DOI: 10.1007/s12648-024-03368-0

V. J. Dagwal

引用次数: 0

A Triangular based determination of temperature using artificial intelligence 利用人工智能进行基于三角形的温度测定

IF 2 4区物理与天体物理

Indian Journal of Physics Pub Date : 2024-08-27 DOI: 10.1007/s12648-024-03381-3

Adeel Tahir, Ahmed Ali Rajput, Mustaqeem Zahid, Shafiq Ur Rehman

{"title":"A Triangular based determination of temperature using artificial intelligence","authors":"Adeel Tahir, Ahmed Ali Rajput, Mustaqeem Zahid, Shafiq Ur Rehman","doi":"10.1007/s12648-024-03381-3","DOIUrl":"https://doi.org/10.1007/s12648-024-03381-3","url":null,"abstract":"The forecasting method emerged in the middle of the twentieth century; its usage has grown exponentially in all aspects of life. More importantly, estimating modern meteorological parameters helps make good decisions regarding weather, health, and agricultural safety measures. Similarly, this study aims to find a better-fitting technique to translate Quetta’s (Pakistan) temperature distribution using its three neighboring stations, Chaman, Kalat, and Sibi. In this regard, a well-known machine learning technique named Artificial Neural Network was utilized. Additionally, four training algorithms are also considered to optimize the model performance. Apart from that, another traditional statistical model is incorporated, which is a Multiple Linear Regression (MLR). Since the temperature distribution has a nonlinear trend, MLR techniques are also useful for making predictions. Machine learning and linear statistical models are provided with seven years of data from 2011 to 2017 for training purposes. Three sets of data for 2018, 2019, and 2020 are fed to determine how these trained models show close agreements with the actual temperature distribution. Different errors are evaluated to assess model performance, such as mean squared error (MSE), mean absolute percentage error (MAPE), mean absolute bias error (MABE), and chi-squared error. ({chi }^{2}), and coefficient of determination (R2). For ANN, the models with the lowest MABE and MAPE values are ANN-RB and ANN-BR, whereas the model with the lowest MSE value, 1.3604, is the ANN-BFG model. The model with the highest correlation is the ANN-BFG model. On the other hand, MLR has an MSE of 1.4253 and a coefficient of determination of 0.9860.","PeriodicalId":584,"journal":{"name":"Indian Journal of Physics","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142215870","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