Brazilian Journal of Physics最新文献_第8页

Quantum Field Theoretical Study of Correlated Quantum Ising Model with Next-Nearest-Neighbour Interaction 具有近邻相互作用的相关量子伊辛模型的量子场理论研究

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-23 DOI: 10.1007/s13538-024-01584-x

Ranjith R. Kumar, Sujit Sarkar

引用次数: 0

The One-Dimensional Gyroidal Superconductor Photonic Crystals Based Cutoff Frequency Tunability for THz Applications 太赫兹应用中基于截止频率可调性的一维陀螺超导体光子晶体

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-22 DOI: 10.1007/s13538-024-01577-w

Ahmed Mehaney, Ahmed M. El-Sherbeeny, Arafa H. Aly, Chittaranjan Nayak, Bhuvneshwer Suthar, Wail Al Zoubi, Mostafa R. Abukhadra, Hussein A. Elsayed

{"title":"The One-Dimensional Gyroidal Superconductor Photonic Crystals Based Cutoff Frequency Tunability for THz Applications","authors":"Ahmed Mehaney, Ahmed M. El-Sherbeeny, Arafa H. Aly, Chittaranjan Nayak, Bhuvneshwer Suthar, Wail Al Zoubi, Mostafa R. Abukhadra, Hussein A. Elsayed","doi":"10.1007/s13538-024-01577-w","DOIUrl":"10.1007/s13538-024-01577-w","url":null,"abstract":"<div>For possible uses in the THz frequency range, we investigated the one-dimensional gyroidal superconductor photonic crystals in the current work. In this regard, each unit cell is designed from gyroidal Bi2Sr2CaCu2O8 (BSCCO) and SrTiO3 layers. Here, BSCCO is embedded in a hosting dielectric medium of SrTiO3 to design the gyroidal layer. The transfer matrix approach and the two-fluid model are both used in the computational analysis of the suggested structure. Studying the optical properties and investigating how several factors, including filling fraction, operating temperature, and layer thicknesses, affect the PC's performance. The results showed the emergence of the cutoff frequency at 5.35 THz. In this regard, the value of the cutoff frequency can be tuned based on the filling fraction, operating temperature, and refractive index of the hosting medium, making the structure promising for optical communication applications.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"54 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193829","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

Decoherence Channels Effects on Thermal Quantum Correlations Within a Two-Dimensional Graphene System 退相干通道对二维石墨烯系统内热量子相关性的影响

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-22 DOI: 10.1007/s13538-024-01585-w

Zakaria Bouafia, Mourad Benzahra, Mostafa Mansour

{"title":"Decoherence Channels Effects on Thermal Quantum Correlations Within a Two-Dimensional Graphene System","authors":"Zakaria Bouafia, Mourad Benzahra, Mostafa Mansour","doi":"10.1007/s13538-024-01585-w","DOIUrl":"10.1007/s13538-024-01585-w","url":null,"abstract":"<div>Two-dimensional graphene systems present considerable advantages for quantum information processing. Electrons within graphene possess not just spin but also additional attributes associated with their specific positions within the lattice and valley index. This study investigates how decoherence channels impact thermal quantum correlations within individual electrons in a two-dimensional graphene system, considering the electron pseudospin and valley index degrees of freedom. Using quantum metrics such as uncertainty-induced non-locality (UIN) and local quantum Fisher information (LQFI), this research evaluates skew-information and non-classical correlations among these extra degrees of freedom of electrons within the graphene system. The dynamics of the intra-particle quantum correlations in graphene’s thermal state is analyzed with respect to factors such as scattering strength, the band structure of graphene, and wavenumber operators. The findings suggest that adjusting the parameters of the graphene system holds promise for enhancing LQFI and UIN, thereby mitigating the adverse effects of increasing equilibrium temperature. Moreover, the study examines how intra-particle thermal quantum correlations evolve under various decoherence channels, including phase damping (PD), phase flip (PF), and amplitude damping (AD). It is observed that under AD and PD channels, both metrics display similar evolution, diminishing as the decoherence parameter increases, with LQFI demonstrating greater resilience compared to UIN. However, distinct behavior is observed when graphene’s thermal state undergoes the PF channel, where both metrics display symmetrical behaviors around the decoherence parameter of (p=0.5).</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"54 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193826","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

Investigation of Hot Press and Cold Press Effects on Structural, Electrical and Magnetic Properties of Pyrene Added Bulk MgB2 研究热压和冷压对添加了芘的块状 MgB2 的结构、电学和磁学特性的影响

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-21 DOI: 10.1007/s13538-024-01586-9

O. Erdem

{"title":"Investigation of Hot Press and Cold Press Effects on Structural, Electrical and Magnetic Properties of Pyrene Added Bulk MgB2","authors":"O. Erdem","doi":"10.1007/s13538-024-01586-9","DOIUrl":"10.1007/s13538-024-01586-9","url":null,"abstract":"<div>In this paper, the effects of hot pressing and cold pressing on the superconducting properties of pyrene (C16H10) added bulk MgB2 were compared. For this aim, the polycrystalline disk-shaped MgB2 samples with addition of 4 wt % C16H10 powder were fabricated by a pellet/closed tube method at 850 °C, after hot pressing at 200 °C and cold pressing. The XRD and SEM results showed that although a-lattice parameters reduce for both C16H10 added samples, the average crystallite size increases after cold pressing because of the accumulation and inhomogeneous distribution of C in the MgB2 structure while it reduces for the C16H10 added hot pressed sample. The resistivity measurements showed that the increment of electron scattering is higher for the C16H10 added cold pressed sample than that of the C16H10 added hot pressed one which shows relatively better grain connectivity, and the Tc values of the samples are not appreciably affected by the pressing conditions. From the magnetisation measurements the in-field Jc values at 10 K and 5.5 T were obtained as 8.41 × 103 A/cm2, 1.62 × 104 A/cm2, 6.90 × 103 A/cm2 and the Hirr values while Jc = 100 A/cm2 at 20 K were obtained as 5.99 T, 6.55 T and 6.19 T for the pure sample and the C16H10 added hot and cold pressed samples, respectively. The higher Jc and Hirr values obtained for the C16H10 added hot pressed sample is because of the homogenous C substitution into MgB2 grains, as compatible with its lower Δρ value, and thus increased flux pinning ability.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"54 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193828","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

Thermoluminescence Spectra of Rare-Earth Doped Calcium Fluoride 掺杂稀土的氟化钙的热致发光光谱

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-17 DOI: 10.1007/s13538-024-01575-y

V. S. M. de Barros, M. E. Yamato, P. L. Guzzo, V. K. Asfora, C. N. P. Oliveira, H. J. Khoury

引用次数: 0

Design of Asymmetric Metamaterial 8-Circular Element Array Antenna for 5G MIMO Applications 为 5G MIMO 应用设计非对称超材料 8 圆元件阵列天线

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-16 DOI: 10.1007/s13538-024-01578-9

B. Rajesh, S. Senthilkumar, U. Surendar, J. William

{"title":"Design of Asymmetric Metamaterial 8-Circular Element Array Antenna for 5G MIMO Applications","authors":"B. Rajesh, S. Senthilkumar, U. Surendar, J. William","doi":"10.1007/s13538-024-01578-9","DOIUrl":"10.1007/s13538-024-01578-9","url":null,"abstract":"<div>A new high gain MIMO array antenna with limited side lobe level between 27.5 and 28.5 GHz is modeled for 5G WLAN applications. The modeled configuration involves two-port MIMO with 8-element array antenna printed on a Rogers RT Duroid-5880 dielectric material. To enhance the antenna’s radiation characteristics, each element in the radiator is excited using corporate inset feeding. The proposed model operates well in the bandwidth of 27.5 to 28.5 GHz, resonating at 28 GHz with a return loss of − 40 dB. For an array configuration, the proposed MIMO array radiator exhibits better limited side lobe level of − 7 dBi (left) and − 4 dBi (right). The MIMO array antenna with a total footprint of 123 × 61 × 0.8 mm3 offers 14 dBi gain in the operating bandwidth. Since the model is configured to be a MIMO antenna, the MIMO attributes such as isolation, TARC, diversity gain, and correlation parameters are analyzed and estimated to be around − 17.25 dB, − 24 dB, 10 dB, and 0.006, respectively, over the band of interest. The proposed model is fabricated and experimentally validated for its simulation results and is found to be in good agreement with simulation results.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"54 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224922","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 Metamaterial Using Waste Materials for Microwave Absorption 利用废弃材料开发超材料以实现微波吸收

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-14 DOI: 10.1007/s13538-024-01571-2

Deeksha Gupta, Prabhakar Kumar, Ashish Dubey, Abhishek Kumar

{"title":"Development of Metamaterial Using Waste Materials for Microwave Absorption","authors":"Deeksha Gupta, Prabhakar Kumar, Ashish Dubey, Abhishek Kumar","doi":"10.1007/s13538-024-01571-2","DOIUrl":"10.1007/s13538-024-01571-2","url":null,"abstract":"<div>The present study focuses on the use of waste materials to generate cost-effective microwave absorption composites. Rice husk (agricultural waste) and exhausted activated charcoal (water filter cartridge waste) were used as waste materials for microwave absorption. Both were blended in different proportions using a planetary ball mill to prepare samples. The XRF and particle size studies were carried out for element and particle size analysis, and for dielectric properties measurement, a vector network analyzer was used. The findings reveal the microwave absorption in the frequency range of 2 to 18 GHz by the blended composites. Sample RHC-11 with 20% exhausted activated charcoal showed a maximum reflection loss of − 38.3 dB at 12 GHz. For further improvement in microwave absorption, the dielectric characteristics of the composites were utilized to develop a layered metamaterial-based microwave absorber. The layered metamaterial is a unique and simple patch design that displays good microwave absorption > 90% and absorbs 99.34% of microwave energy at 16 GHz frequency. The developed metamaterial-based microwave absorber shows an absorption bandwidth of 6.60 GHz with a thickness of 2.3 mm. In addition, the proposed structure is independent of the oblique incidence angle and polarization angle.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"54 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193832","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

The Strong Thermally and Optically Stimulated Luminescence of Solonópole (Ceará, Brazil) Natural Quartz: Comparing Records and Proposing New Insights 索洛诺波尔（巴西塞阿拉）天然石英的强热激发和光激发发光：比较记录并提出新见解

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-14 DOI: 10.1007/s13538-024-01573-0

Pedro L. Guzzo, Bruno R. Soares, Fania D. Caicedo Mateus, Viviane K. Asfora, Leonardo B. Ferreira de Souza, Helen J. Khoury

{"title":"The Strong Thermally and Optically Stimulated Luminescence of Solonópole (Ceará, Brazil) Natural Quartz: Comparing Records and Proposing New Insights","authors":"Pedro L. Guzzo, Bruno R. Soares, Fania D. Caicedo Mateus, Viviane K. Asfora, Leonardo B. Ferreira de Souza, Helen J. Khoury","doi":"10.1007/s13538-024-01573-0","DOIUrl":"10.1007/s13538-024-01573-0","url":null,"abstract":"<div>Quartz plays a crucial role in retrospective dosimetry and dating inquiries in Quaternary Science. The success of thermally and optically stimulated luminescence (TL, OSL) methods depends on the signal repeatability and the signal intensity of quartz grains. Among numerous crystals investigated in the last 20 years, few pieces collected from pegmatitic deposits located near the Solonópole municipality (Ceará State) have shown a notable brightness after being sensitized with a method combining high dose γ radiation and moderate heat treatments. To examine this trend, this paper reviews TL and OSL records measured in six single crystals with different sensitivities by means of different equipment setups and a wide range of γ and β radiation doses. TL emission spectra and trace-element analyses are shown and used to further discuss the complex problem involving electron traps, luminescence centers, and impurity-related point defects into the lattice of quartz. Electron–hole transferring in association with Li+ motion through trapping and recombination centers related to Ge and Al impurities appear to be the basis for a model to explain the brightness of Solonópole samples. This study shows the importance of adopting samples in the single crystal form to further investigate TL and OSL signal properties in quartz.</div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"54 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193837","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

Electron Spin Resonance Dating of Shells—A Systematic Literature Review 贝壳电子自旋共振定年--系统性文献综述

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-14 DOI: 10.1007/s13538-024-01569-w

Angela Kinoshita, Renato Pereira Lopes, Oswaldo Baffa

引用次数: 0

Dynamical Conductivities for the Fermionic Lieb Lattice 费米子利布晶格的动态传导性

IF 1.5 4区物理与天体物理

Brazilian Journal of Physics Pub Date : 2024-08-14 DOI: 10.1007/s13538-024-01574-z

A. S. T. Pires

引用次数: 0