The European Physical Journal B最新文献

{"title":"Acoustoelectric effect in bilayer graphene due to intrinsic deformation potential and extrinsic piezoelectric phonon couplings","authors":"Subhana Nafees,&nbsp;S. S. Z. Ashraf","doi":"10.1140/epjb/s10051-025-00981-8","DOIUrl":"10.1140/epjb/s10051-025-00981-8","url":null,"abstract":"<div><p>Bilayer graphene (BLG) has been found to exhibit electronic properties that are either altogether unique to it, or if similar to single-layer graphene (SLG) then they differ in character and intensity. In this article, we focus our investigation on the amplification/attenuation and acoustoelectric current phenomena in BLG generated through piezoelectric and deformation potential electron–phonon coupling mechanisms. We conducted a comprehensive exploration of the kinetic equations within the Boltzmann transport framework, examining both analytical and numerical estimation of the acoustoelectric current and amplification coefficient. Notably, we observe a noteworthy change in the generation of acoustoelectric current in BLG that occurs at much lower (KHz) frequencies as compared to SLG, where the current of the same magnitude occurred at the MHz frequency range. Also, the acoustoelectric current in BLG follows a linear relationship with frequency <span>(({omega }_{q}))</span>.</p><h3>Graphical abstract</h3><p>Schematics of a bilayer graphene sheet placed on a piezoelectric substrate (GaAs) between two IDT devices. A surface acoustic waves (SAW) is generated by a high-frequency signal input to IDT1 formed on a piezoelectric substrate which reaches IDT2 where it is converted back into high frequency signal for detection. When a SAW propagates in graphene, an acoustoelectric current (<span>({I}_{AEB})</span>) flows between two attached electrodes.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145167224","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":"Ising ferromagnet and nonadditive entropies: equilibrium and nonequilibrium properties","authors":"Henrique Santos Lima,&nbsp;Constantino Tsallis","doi":"10.1140/epjb/s10051-025-00980-9","DOIUrl":"10.1140/epjb/s10051-025-00980-9","url":null,"abstract":"<p>Some equilibrium and nonequilibrium properties of the one-dimensional nearest-neighbor Ising ferromagnet that are grounded on nonadditive entropies are reviewed. First, we focus on the known fact that the nonadditive entropy <span>(S_q)</span> for a special value of <i>q</i>, namely <span>(q^star =sqrt{37}-6 simeq 0.0828)</span>, yields entropic extensivity, thus satisfying the Legendre structure of classical thermodynamics, at the quantum critical point of the spin-1/2 ferromagnetic Ising chain in the presence of an external transverse field. Then we address a well-known issue in phase transitions, namely that, at the critical point, quantities such as the susceptibility and the Grüneisen ratio diverge within Boltzmann–Gibbs statistical mechanics (<span>(q=1)</span>). Moreover, we show that such thermostatistical quantities diverge for <span>(q&gt;q^star )</span>, vanish for <span>(q&lt;q^star )</span>, and are <i>finite</i> for <span>(q=q^star )</span>. Second, we focus on a transport phenomenon, specifically, the heat transport in a one-dimensional Ising model. We do so by analyzing two classical inertial anisotropic <i>XY</i> models that recover the equilibrium and nonequilibrium properties of the Ising model under the extreme anisotropy limit. In other words, we determine, from first principles, the thermal conductivity behavior of the Ising chain with regard to temperature and lattice size, concluding that the model exhibits normal heat conduction, i.e., it satisfies Fourier’s law.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165946","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":"Probing Cs2OsX6 (X = Cl, Br, I) double perovskites via DFT: prospects for photocatalytic water splitting and CO2 reduction","authors":"Mohamed El Amine El Goutni,&nbsp;Abedrahmane Remil,&nbsp;Mokhtare Saidi,&nbsp;Mohamed Batouche,&nbsp;Taib Seddik","doi":"10.1140/epjb/s10051-025-00979-2","DOIUrl":"10.1140/epjb/s10051-025-00979-2","url":null,"abstract":"<div><p>This study presents a comprehensive theoretical investigation of the structural, electronic, mechanical, and optical properties of Cs₂OsX₆ (X = Cl, Br, I) vacancy-ordered double perovskites using density functional theory (DFT) within the WIEN2k computational framework. The structural stability of Cs₂OsX₆ compounds was systematically evaluated through calculations of total ground state energy, cohesive energy, and formation energy, revealing remarkable stability under ambient conditions and favorable synthesis conditions. Mechanical property assessments, including Cauchy pressure and Poisson's ratio, indicated predominantly ductile behavior, suggesting excellent mechanical durability. Electronic structure calculations, performed using the Wu and Cohen generalized gradient approximation (WC-GGA) and the Tran–Blaha modified Becke–Johnson (TB-mBJ) methods, revealed semiconducting behavior with direct bandgaps of 1.98 eV (Cs₂OsCl₆), 1.68 eV (Cs₂OsX₆), and 0.91 eV (Cs₂OsI₆). Optical property analysis demonstrated strong absorption in the visible spectrum, with Cs₂OsI₆ exhibiting superior light-harvesting capabilities. Exciton binding energy calculations showed a decreasing trend with increasing halide atomic size, indicating enhanced charge carrier separation and reduced recombination rates. Band edge alignment suggested that Cs₂OsCl₆ and Cs₂OsX₆ are suitable for water oxidation, while Cs₂OsI₆ shows potential for CO₂ reduction. These findings provide a robust theoretical foundation for the design and optimization of Cs₂OsX₆ perovskites in next-generation optoelectronic and photocatalytic devices, advancing sustainable energy technologies.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165525","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":"Magnetic map of Cr adatom, Cr dimer and Cr–O on Co(0001) hcp: first principles calculations","authors":"J. C. Ávila-Gaxiola,&nbsp;M. E. E. Ávila-Gaxiola,&nbsp;J. G. Ibarra-Armenta,&nbsp;S. Meza-Aguilar","doi":"10.1140/epjb/s10051-025-00971-w","DOIUrl":"10.1140/epjb/s10051-025-00971-w","url":null,"abstract":"<p>Magnetism of Cr adatom, Cr dimer and Cr–O on Co(0001) hcp substrate is studied on the basis of density functional theory using Quantum Espresso code. The most stable geometry occurs when Cr is adsorbed in the most highly coordinated sites. Cr adatom couples antiferromagnetically with the Co atoms and shows a high magnetic moment of 4.57 <span>(mu _B)</span>. Cr dimer also couples antiferromagnetically with the Co atoms, shows a magnetic moment of 4.50 <span>(mu _B)</span> for both Cr atoms and increases its interatomic distance to minimize its energy. For the Cr–O, the most stable state is when the Cr atom is coupled antiferromagnetically with Co substrate atoms. The effect of O atom decreases the Cr and Co atomic magnetic moments for the first nearest neighbors. For Cr–O, calculations were performed with DFT and DFT+U approaches because oxygen is not well described by DFT-only. The DFT+U increases the interatomic distances and magnetic moments on Cr and its Co nearest neighbors.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166128","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":"Coarsening in the long-range Ising model with conserved dynamics","authors":"Subir K. Das,&nbsp;Soumik Ghosh","doi":"10.1140/epjb/s10051-025-00972-9","DOIUrl":"10.1140/epjb/s10051-025-00972-9","url":null,"abstract":"<p>While the kinetics of domain growth, even for conserved order-parameter dynamics, is widely studied for short-range inter-particle interactions, systems having long-range interactions are receiving attention only recently. Here, we present results, for such dynamics, from a Monte Carlo (MC) study of the two-dimensional long-range Ising model, with focus on critical compositions of up and down spins. The order parameter in the MC simulations was conserved via the incorporation of the Kawasaki spin-exchange method. The simulation results for domain growth, following quenches of the homogeneous systems to temperatures below the critical values <span>(T_c)</span>, were analyzed via a method analogous to the finite-size scaling technique of equilibrium critical phenomena and other advanced methods. The outcomes reveal that the growths follow power laws, with the exponent having interesting dependence on the range of interaction. Quite interestingly, when the range is above a cut-off, the exponent, for any given range, seems to change from a larger value to a smaller one, during the evolution process. While the corresponding values at late times match with certain theoretical predictions for the conserved order-parameter dynamics, the ones at the early times appear surprisingly high, often quite close to even the theoretical values for the nonconserved case.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165590","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":"Progress of high-temperature superconducting joints","authors":"Yalin Yan,&nbsp;Dongliang Wang,&nbsp;Yancang Zhu,&nbsp;Xianping Zhang,&nbsp;Pengyu Bai,&nbsp;Yanwei Ma","doi":"10.1140/epjb/s10051-025-00976-5","DOIUrl":"10.1140/epjb/s10051-025-00976-5","url":null,"abstract":"<div><p>The increasing resolution of Magnetic Resonance Imaging (MRI) and Nuclear Magnetic Resonance (NMR) spectrometers requires the use of superconducting magnets to generate higher magnetic field strength. Since the magnetic field limit of Nb₃Sn/NbTi low-temperature superconductor (LTS) coils is about 1 GHz (23.5 T), high-temperature superconductors (HTS) with excellent high-field properties have been increasingly used in superconducting coils to increase the magnetic field strength of NMR magnets. The persistent current mode (PM) of superconducting magnets requires uninterrupted current flow in the coils, maintaining strength without external power. Therefore, achieving low resistance in the joints between coils, ideally resulting in a superconducting joint, is crucial. Creating superconducting joints in high-temperature superconductors presents challenges, with significant effort directed toward overcoming them. This paper provides an overview of the preparation technologies for superconducting joints, such as ReBa₂Cu₃O_<i>y</i> (REBCO, RE = rare earth), BiSrCaCuO (Bi2212, Bi2223), Iron-based Superconductors (IBS), and MgB₂. By reviewing the latest advancements to key issues and conducting an in-depth analysis of the technical characteristics of different process schemes in various types of superconducting joints, this article offers valuable references for the preparation of superconducting joints.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165224","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 effect of time-dependent mass on the dynamics of Brownian particles","authors":"Serhat F. Özeren","doi":"10.1140/epjb/s10051-025-00975-6","DOIUrl":"10.1140/epjb/s10051-025-00975-6","url":null,"abstract":"<div><p>This research investigates the behavior of particles with time-dependent mass, which increases exponentially toward a limit value, within the framework of Brownian motion. The study employs the Langevin model to analyze the effects on mean squared displacement and velocity distributions of these particles. Solutions are provided specifically for the white noise case, examining the changes in the mean squared displacement and mean squared velocity as the mass increases. Consistent with physical reality, it has been observed that an increase in mass results in a reduced rate of displacement of particles from their initial position. As a result of the fluctuation–dissipation theorem, it is demonstrated that the change in mass affects the equilibrium state between the intensity of the external force and the damping parameter. Theoretical results are evaluated through graphical representations, offering a detailed discussion on the impact of mass variation on particle dynamics. This approach provides significant insights into how time-dependent mass variations influence particle motion.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><img></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164890","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":"Magnetotransport of Cd3As2 thin films under a tilted magnetic field","authors":"Rui Min,&nbsp;Yi-Xiang Wang","doi":"10.1140/epjb/s10051-025-00969-4","DOIUrl":"10.1140/epjb/s10051-025-00969-4","url":null,"abstract":"<div><p>The bulk Cd₃As₂ is a prototype Dirac semimetal and its thin films have been successfully fabricated in recent experiments. The subsequent magnetotransport studies revealed several exotic topological phases, such as two-dimensional (2D) topological insulator phase and 2D Weyl semimetal phase. Here, we make a theoretical study on the magnetotransport properties of Cd₃As₂ thin films under a tilted magnetic field. Within the effective <span>(kcdot p)</span> model describing the low-energy excitations in Cd₃As₂, we find that when the out-of-plane magnetic field component is small, each <span>(nge 1)</span> LLs own the twofold degeneracy, and the Hall plateau shows the odd-integer sequence; when the out-of-plane component increases, the LL spacings get enlarged, which breaks the twofold degeneracy of the LLs and leads to the integer sequence of the Hall plateaus. Therefore, our work could capture the main physics underlying the tilt angle-driven Hall plateau transitions that are observed in the experiment.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164203","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":"Sensitivity exploration of micropolar fluid through porous permeable walls using ANN","authors":"P. M. Renupriya,&nbsp;M. Muthtamilselvan,&nbsp;D. Prakash,&nbsp;Ikhyun Kim","doi":"10.1140/epjb/s10051-025-00974-7","DOIUrl":"10.1140/epjb/s10051-025-00974-7","url":null,"abstract":"<div><p>This paper investigates the heat transfer process in a two-dimensional flow of a micropolar fluid through porous permeable walls under a constant heat flux condition. To simplify the problem, a similarity transformation is applied, converting into a set of nonlinear boundary value problems. The Runge–Kutta–Fehlberg (RKF) method is then used to derive the series solutions for key variables such as microrotation, velocity, concentration distributions, and temperature. The study also explores the influence of several important parameters, including Reynolds number, magnetic and radiation parameter, Prandtl number, and Peclet numbers for mass and heat transfer. Through the use of response surface methodology (RSM), sensitivity analysis, and artificial neural networks (ANN), the research demonstrates that the system is well defined and behaves predictably. The study includes a range of graphical representations, such as residual contour and surface plots, which help to visualize and analyze the key components of the flow field. Additionally, tables are provided to present the results more clearly, allowing for a deeper understanding of how various parameters influence the system’s behavior.</p></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164891","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":"Impact of hematite surface magnetic configurations and strain on O2 adsorption","authors":"Wala Elsayed,&nbsp;Abdulrafiu Tunde Raji,&nbsp;Omololu Akin-Ojo,&nbsp;Nataša Stojić,&nbsp;Nicola Seriani","doi":"10.1140/epjb/s10051-025-00978-3","DOIUrl":"10.1140/epjb/s10051-025-00978-3","url":null,"abstract":"<div><p>Iron oxides are abundant and inexpensive materials with promising potential for catalysis. However, the influence of their intrinsic magnetic properties on their catalytic activity is not well established. This study investigates the correlation of magnetic order to the catalytic activity of the α-Fe₂O₃ (0001) surface using the adsorption of molecular oxygen as a descriptor. Our findings reveal that the magnetic order strongly influences the O₂ adsorption, yielding lower binding energies for the antiferromagnetic (AFM) configurations and making them more inert than the ferromagnetic (FM) one. We find the origin of the higher reactivity of the FM configuration in its broader d-band and its delocalization of the charge, together with the larger surface magnetization, relative to the AFM ones. Adsorption on the FM surface results in a markedly higher charge transfer to O₂ than on the AFM surfaces. These results highlight the critical role of magnetic configurations in governing the adsorption and catalytic properties of α-Fe₂O₃ (0001) surfaces, providing valuable insights for designing and optimizing more efficient magnetic catalysts. We also investigated the adsorption energy as a function of biaxial strain, finding that compressive strain strengthens adsorption on both FM and AFM surfaces, with the FM surface gaining additional stability relative to the AFM surface under compressive strain.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 6","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164733","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}