Adriane Marques de Souza Franco, Isabela de Oliveira, Markus Fraenz, Ezequiel Echer, Mauricio José Alves Bolzan, João Carlos de Moura Castro Neto
{"title":"Wave Mode Occurrence Distribution Around Venus: A VEX Statistical Study","authors":"Adriane Marques de Souza Franco, Isabela de Oliveira, Markus Fraenz, Ezequiel Echer, Mauricio José Alves Bolzan, João Carlos de Moura Castro Neto","doi":"10.1007/s13538-025-01723-y","DOIUrl":"10.1007/s13538-025-01723-y","url":null,"abstract":"<div><p>In this work, plasma and magnetic field data from Venus Express (VEX) were analyzed through the entire mission span (2006-2014) in order to statistically study wave mode occurrence around Venus considering different solar wind conditions. The wave mode occurrence distribution in terms of solar activity (maxima and minimum periods), solar wind pressure, and interplanetary magnetic field (IMF) east-west component orientation (<span>(B_{y}>0)</span> and <span>(B_{y}<0)</span>) were computed. Our results reveal that mirror mode occurrence does not seems to be affected by changes in the analyzed parameters. The most significant influence was observed in the Alfvén mode by the solar wind dynamic pressure, which has its occurrence rate clearly increased, during periods of high solar wind dynamic pressure. The fast mode seems to be influenced by the three analyzed parameters and tends to occur more often during periods of positive IMF <span>(B_{y})</span> and high solar activity. Further, a higher occurrence of fast wave mode during enhanced dynamic pressure was observed, which may be related to KH instability.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527654","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}
Nicolai Popov, William J. Briscoe, Igor Strakovsky
{"title":"CP Violation Problem","authors":"Nicolai Popov, William J. Briscoe, Igor Strakovsky","doi":"10.1007/s13538-025-01729-6","DOIUrl":"10.1007/s13538-025-01729-6","url":null,"abstract":"<div><p>The CP violation problem has a long history emanating from its discovery 60 years ago in the decay of neutral kaons and subsequent experimental and theoretical studies over several decades. We review herein experimental data that observe indirect CP violation of the order of <span>(sim 10^{-3})</span>, as well as the discovery of direct CP violation of the order of <span>(sim 10^{-6})</span>. Despite improved experimental methods over the past half a century, the original CP violation numbers have remained the same. Verification of the CP violation in the decay of charged kaons was also observed. Data reflecting CP violation in the decays of <i>B</i> and <i>D</i> mesons have become very important and are also discussed in this review. The question of CP violation only with the participation of <span>(sbar{s})</span>, <span>(cbar{c})</span>, and <span>(bbar{b})</span> quarks in the framework of the Standard Model or beyond it and its small magnitude remains open.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527653","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":"Design of all-Optical Transmission Gate Using Silicon Microring Resonator","authors":"Jayanta Kumar Rakshit, Premkumar Selvam, Selvakumarasamy Kathirvelu, Sultan Mahaboob Basha, Kalimuddin Mondal, Vankadari Nagaraju, Bhaskarrao Yakkala, Manjur Hossain","doi":"10.1007/s13538-025-01730-z","DOIUrl":"10.1007/s13538-025-01730-z","url":null,"abstract":"<div><p>Proposed manuscript includes the implementation of all-optical transmission gate employing silicon microring resonator. A replacement for traditional CMOS technology, large-scale optical integrated circuits are being considered due to the increasing need for ultra-fast terahertz data processing and transfer. In addition, energy-efficient circuits are becoming more and more crucial. The architecture is analyzed at about 260 Gbps using MATLAB. Networks for optical signal processing can be constructed using all-optical transmission gates as building blocks. Proposed transmission gate is also utilized in the design of a 2:1 multiplexer. The evaluation of a few performance-indicating variables includes “extinction ratio (ER)”, “contrast ratio (CR)”, “amplitude modulation (AM)”, “on–off ratio (OOR)”, and “relative eye opening”. At low average pump power of 1.18 mW, proposed model has high ER, CR, and OOR of 26.78, 31.39, and 36.8 dB, respectively. Computed AM is recorded as 0.22 dB. Optimized design parameters are chosen to utilize the design practically.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513284","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}
Sudhansu Sekhar Hota, Debasish Panda, R. N. P. Choudhary
{"title":"Synthesis and Characterization of Co-doped (Li/W) Distorted Perovskite Bismuth Manganite (Bi1/2Li1/2)(Mn1/2W1/2)O3 for Electronic Devices","authors":"Sudhansu Sekhar Hota, Debasish Panda, R. N. P. Choudhary","doi":"10.1007/s13538-025-01726-9","DOIUrl":"10.1007/s13538-025-01726-9","url":null,"abstract":"<div><p>In this paper, structural, surface, capacitive, and transport characteristics of newly designed co-doped (Li<sup>+</sup>/W<sup>6+</sup>) distorted perovskite bismuth manganite of a composition (Bi<sub>1/2</sub>Li<sub>1/2</sub>)(Mn<sub>1/2</sub>W<sub>1/2</sub>)O<sub>3</sub> have been reported. The structural analysis of the material using X-ray diffraction data determines distorted perovskite monoclinic structure with unit cell dimensions of <i>a</i> = 8.4642 Å, <i>b</i> = 12.5179 Å, <i>c</i> = 8.2215 Å, <i>V</i> = 869.04 Å<sup>3</sup>, and <i>β</i> = 93.96°. Analysis of vibrational molecular bands of Raman and Fourier transform infrared spectroscopy (FTIR) spectra shows the inclusion/doping of Li<sup>+</sup>/W<sup>6+</sup> ions in the parent compound (bismuth manganite). A detailed study of impedance spectroscopy data shows the existence of a non-Debye relaxation mechanism indicating negative temperature coefficient of resistance (NTCR) behavior in the compound. Conductivity analysis shed light on the existence of charge transport mechanism and correlated barrier hopping process in the material. The hysteresis loops suggest the existence of ferroelectric properties in the material. In conclusion, this synthesized material shows excellent potential (TCR = − 1.3%/°C) for temperature-based applications.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513282","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}
A. Khatar, B. Bouadjemi, M. Houari, M. Matougui, T. Lantri, K. Kelifa-Kerfa, S. Bentata, S. Haid, M. H. Cherif, A. Messaoudi, S. Mesbah
{"title":"Spin-Gapless Quaternary Heusler Alloys IrCoTiZ (Z = Si, Sn, Pb): Exploring New Opportunities in Spintronics, Optoelectronics, and Thermoelectrics","authors":"A. Khatar, B. Bouadjemi, M. Houari, M. Matougui, T. Lantri, K. Kelifa-Kerfa, S. Bentata, S. Haid, M. H. Cherif, A. Messaoudi, S. Mesbah","doi":"10.1007/s13538-025-01725-w","DOIUrl":"10.1007/s13538-025-01725-w","url":null,"abstract":"<div><p>This study explores the structural, electrical, magnetic, optical, and thermoelectric properties of quaternary Heusler alloys IrCoTiZ (Z = Si, Sn, Pb) through first-principals calculations using Wien2K computational package. These materials exhibit strong potential for high-temperature spintronic applications, owing to the stability of their ferromagnetic phase, with predicted Curie temperatures surpassing room temperature. The electronic structure analysis indicates a semiconducting band gap in the spin-down channel, while the spin-up channel retains metallic behaviour. Notably, IrCoTiSi demonstrates high absorption in both the visible and ultraviolet regions, highlighting its potential for optoelectronic applications. Thermoelectric analysis indicates that IrCoTiPb and IrCoTiSn behave as p-type materials, whereas IrCoTiSi exhibits a mixed n-type and p-type character. Although the thermoelectric efficiency is moderate at low to mid-range temperatures, the unique combination of spin-gapless semiconducting properties in these alloys highlights their potential for advancing spintronics, optoelectronics, and thermoelectric applications.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489499","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}
Andrés Fernando Castillo Ramírez, John Morales Aponte, Teirungumu Apolinar Torres Zalabata
{"title":"Geometry Underlying of the Gauge Principle","authors":"Andrés Fernando Castillo Ramírez, John Morales Aponte, Teirungumu Apolinar Torres Zalabata","doi":"10.1007/s13538-024-01677-7","DOIUrl":"10.1007/s13538-024-01677-7","url":null,"abstract":"<div><p>In this study, we investigate the underlying geometry of the gauge principle as an alternative way for understanding particle interactions. We employ the linear sigma model, based on the global–local symmetry group <span>(O(N+1))</span>, reducing to <i>O</i>(<i>N</i>) after a procedure of spontaneous symmetry breaking. We illustrate how the dynamics of the Goldstone bosons—arising from the spontaneous symmetry breaking—are governed by the covariant derivative, which is derived from first principles using Killing vectors notion. Besides, we analyze how the internal space acquires a curvature when locality concept is demanded into the theory. The curvature tensor for the manifold of the internal space is precisely the field strength tensor, which is used to formulate the kinetic term of the bosons in gauge quantum field theories.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481066","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}
M. A. H. Talukder, M. K. Islam, M. S. Munir, M. Salahuddin
{"title":"Electrostatic Dust Modes in Magnetized Dusty Plasma with Crucial Condition of Dust Lower Hybrid Mode","authors":"M. A. H. Talukder, M. K. Islam, M. S. Munir, M. Salahuddin","doi":"10.1007/s13538-025-01727-8","DOIUrl":"10.1007/s13538-025-01727-8","url":null,"abstract":"<div><p>Electrostatic dust modes in magnetized dusty plasma with massive negatively charged dust grains are theoretically investigated using the fluid treatment of plasma. A general dispersion relation for dust modes is derived. Dust-acoustic (DA), ion-acoustic (IA), dust-lower-hybrid (DLH), and ion cyclotron (IC) modes are obtained by applying appropriate plasma conditions to the dispersion relation for the respective dust modes. The phase velocity of the DLH mode is found to be lower than that of the DA, IA, and IC modes. It is also observed that a crucial condition is required to be satisfied to excite DLH mode in laboratory experiment. Behavior of the dust modes is graphically illustrated using the values of appropriate dusty plasma parameters.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481067","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}
Wan Faezah Wan Azmi, Ahmad Qushairi Mohamad, Lim Yeou Jiann, Sharidan Shafie
{"title":"Mathematical Modelling on Pulsative MHD Blood Casson Nanofluid in Slip and Porous Capillaries for Nano-cryosurgery with Caputo-Fabrizio Approach","authors":"Wan Faezah Wan Azmi, Ahmad Qushairi Mohamad, Lim Yeou Jiann, Sharidan Shafie","doi":"10.1007/s13538-025-01701-4","DOIUrl":"10.1007/s13538-025-01701-4","url":null,"abstract":"<div><p>Nano-cryosurgery is a novel approach to treating tumours that integrates cryosurgery and nanotechnology. Researchers are interested in nano-cryosurgery since it minimises damage to healthy surrounding tissue, bleeding, and post-surgery complications. However, conducting experimental research requires a lot of time and money. Hence, the mathematical model developed for blood flow with nanoparticles is significant for nano-cryosurgical treatments. The present study aims to investigate analytically the fractional derivative approach of blood nanofluid flow in the porous medium of a slip cylinder. The effects of pulsatile pressure gradient, MHD, and free convection flow are being considered. Blood nanofluid is modelled with a Casson fluid model dispersed with gold nanoparticles. The Caputo-Fabrizio fractional derivative approach, known for its dimensional consistency through normalisation, is employed in the momentum and energy equations. Then, dimensionless governing equations are obtained by employing the dimensionless variables. The problem is solved by combining the Laplace and finite Hankel transforms to obtain velocity and temperature expressions. The present study graphically illustrates and discusses the effects of various related parameters on the velocity and temperature profiles. The research findings revealed that the slip velocity significantly impacts the blood nanofluid flow at the cylinder’s wall. The fractional model of blood nanofluid is more sensible and accurate than the classical model. The results are essential for optimising the nano-cryosurgery procedure by controlling the ice formation and orientation, heat transfer mechanism between cryoprobe and cells, cryogenic agent delivery, and freezing and thawing time.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 3","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471846","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}
Sandip M. Parkhi, Shaukat A. Shah, Shruti P. Dhale, Nilesh S. Ugemuge
{"title":"Synthesis and Spectroscopic Analysis of Bi2Al4O9:Tb3+ Phosphor for Optical Applications","authors":"Sandip M. Parkhi, Shaukat A. Shah, Shruti P. Dhale, Nilesh S. Ugemuge","doi":"10.1007/s13538-025-01722-z","DOIUrl":"10.1007/s13538-025-01722-z","url":null,"abstract":"<p>Using urea as fuel, a solution combustion synthesis process was employed to prepare pristine and Tb<sup>3+</sup><b>-</b>doped Bi<sub>2</sub>Al<sub>4</sub>O<sub>9</sub> phosphor. Using powder XRD, the produced material’s orthorhombic mullite-type structure with Pbam (55) space group was confirmed. SEM and EDS were used to evaluate the sample’s morphology and chemical composition. The Hitachi F-7100 fluorescence spectrophotometer was used to record lifespan and photoluminescence measurements. The PL spectra of Bi<sub>2</sub>Al<sub>4</sub>O<sub>9</sub>:Tb<sup>3+</sup> exhibited a significant cyan-blue emission with the highest emission occurring around 545 nm for excitation wavelength 285 nm attributed to <sup>5</sup>D<sub>4</sub> → <sup>7</sup>F<sub>j</sub> (j = 0 to 6) transitions. Synthesized phosphor has potential applications in field emission display systems and solid-state lighting (Mater. Today. Proc. 18: 1132-1137 (2019)).</p>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 2","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13538-025-01722-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446452","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}
Mario A. Camargo, Lucas L. Kozlinskei, Eder C. F. de Souza, Sandra R. M. Antunes, Luiz F. Pires
{"title":"Effect of Temperature and Addition of Hematite on the Porous System of Foamed Glass Analysed by X-ray Microtomography","authors":"Mario A. Camargo, Lucas L. Kozlinskei, Eder C. F. de Souza, Sandra R. M. Antunes, Luiz F. Pires","doi":"10.1007/s13538-025-01721-0","DOIUrl":"10.1007/s13538-025-01721-0","url":null,"abstract":"<div><p>Foamed glass is an interesting material that can be used as a thermal insulator. Additives (e.g., hematite) and thermal treatments can affect the material structure when producing foamed glass. As a consequence, the foamed glass pore system can be changed. In this study, we propose the use of X-ray microtomography to characterise the porous system of foamed glass produced with 10% (by mass) of foaming agent (dolomitic limestone) and the addition of 1% to 10% (by mass) hematite and subjected to thermal treatments of 730 or 760 °C for 2 h. Emphasis was given on the effect of the studied conditions on pore size distribution and pore connectivity. Overall, the results show that adding hematite concentrates the pores in smaller size ranges. Increasing the temperature favours the formation of pores in a broader range of sizes. Even with the pores concentrated in a narrow size range (< 200 µm), the pores showed high connectivity after adding 5% and 10% hematite (both thermal treatment temperatures). The pores were found to show good connectivity for the lower hematite concentrations but for a broader range of pore sizes. The imaged porosity showed variations from c. 63%—84%. The anisotropy values (dimensionless number ranging from 0.04—0.15) indicate the existence of isotropic structures, while the tortuosity values (dimensionless number ranging from 1.13 to 1.23) show pores with low tortuosity. Thus, X-ray microtomography can track changes in the micromorphological properties that result from the addition of hematite and different heat treatments in foamed glass.</p></div>","PeriodicalId":499,"journal":{"name":"Brazilian Journal of Physics","volume":"55 2","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13538-025-01721-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446451","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}