The European Physical Journal B最新文献

{"title":"Investigation of the high-pressure effects on the electronic structure and dielectric properties of CsF: a first-principles study","authors":"Yassine Tamerabet,&nbsp;Mohamed Khedidji,&nbsp;Houssyen Yousfi,&nbsp;Mohamed Trari,&nbsp;Toufik Bentrcia","doi":"10.1140/epjb/s10051-025-01079-x","DOIUrl":"10.1140/epjb/s10051-025-01079-x","url":null,"abstract":"<div><p>Cesium fluoride (CsF), a prototypical ionic compound with a wide band gap, is of pivotal importance for numerous technological applications. However, its large band gap hinders its functional integration into optoelectronic devices requiring semiconductor properties. The aim of this work is to present a first-principles investigation of the structural, electronic, and dielectric properties of cubic CsF under hydrostatic pressure, using density functional theory within the generalized gradient approximation. Our findings demonstrate a progressive reduction of the band gap from 5.41 eV at ambient conditions to 2.40 eV at 105 GPa, associated with a transition from an indirect gap at zero pressure to a direct gap at high pressure. Analysis of the density of states reveals enhanced s–p hybridization between Cs 6s, and F 2<i>p</i> orbitals under compression, which drives the electronic evolution. In parallel, we observe a significant alteration of the dielectric properties with pressure. The Born effective charges and the electronic part of the dielectric tensor increase monotonically under compression, whereas the ionic part first decreases and then the trend reverses and grows slowly beyond 25 GPa, reflecting complex changes in lattice dynamics. These outcomes provide new insights into the pressure-dependent behavior of CsF and elucidate the potential of external compression as a tool to tune its electronic and dielectric properties for emerging functional applications.</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 11","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145456575","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":"Ternary equiatomic intermetallic superconductors: structures, pairing mechanisms, and emerging phenomena","authors":"Paromita Pramanik,&nbsp;Atasi Bhattacharjee,&nbsp;Sushmita Biswas,&nbsp;Supriya Pal,&nbsp;Sohini Mitra,&nbsp;Meghna Maity,&nbsp;Amitava Bhattacharyya","doi":"10.1140/epjb/s10051-025-01076-0","DOIUrl":"10.1140/epjb/s10051-025-01076-0","url":null,"abstract":"<p>Ternary equiatomic intermetallic superconductors exhibit a striking range of superconducting behaviors, offering insights into the interplay of crystal structure, spin–orbit coupling (SOC), and electronic interactions. While 111-based systems such as ZrRuAs and HfRuP show conventional s-wave pairing, compounds like TaRuSi and NbRuSi suggest unconventional, potentially spin-triplet states. Multiband effects are common, with centrosymmetric versus non-centrosymmetric lattices critically influencing pairing mechanisms. In non-centrosymmetric systems, antisymmetric SOC mixes singlet and triplet channels, and strong SOC in 4<i>d</i> and 5<i>d</i> metals opens a pathway to topological superconductivity. Observations of time-reversal symmetry breaking and anomalous upper critical fields indicate complex order parameters beyond BCS theory. This review synthesizes current understanding, highlighting how structural and electronic diversity generates superconducting states from fully gapped to potentially topological, providing a framework for both fundamental studies and the discovery of novel quantum materials.</p><p>Ternary equiatomic superconductors exhibit diverse pairing mechanisms, influenced by crystal structure, spin–orbit coupling, and electronic interactions. Their unique properties, including unconventional superconductivity and time-reversal symmetry breaking, provide insights into topological and multiband effects, shaping future materials and applications.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 11","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435868","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":"Hysteresis in magnets","authors":"Deepak Dhar,&nbsp;Sanjib Sabhapandit","doi":"10.1140/epjb/s10051-025-01078-y","DOIUrl":"10.1140/epjb/s10051-025-01078-y","url":null,"abstract":"<p>We provide an overview of studies of hysteresis in models of magnets. We discuss the shape of the hysteresis loop, dynamical symmetry breaking, and the dependence of the area of the loop on the amplitude and frequency of the driving field. We also discuss Barkhausen noise in the hysteresis loops, where the wide distribution of sizes of magnetization jumps may be modeled by the random field Ising model. We discuss the distribution of sizes of these jumps in the random field Ising model on the Bethe lattice.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 11","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435867","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":"Canine preictal topology: ordinal complexity and neural mapping","authors":"Mauro Granado,&nbsp;Nataniel Martinez,&nbsp;Federico Miceli,&nbsp;Osvaldo A. Rosso,&nbsp;Fernando Montani","doi":"10.1140/epjb/s10051-025-01074-2","DOIUrl":"10.1140/epjb/s10051-025-01074-2","url":null,"abstract":"<p>This research explores the identification of preictal biomarkers in canine epilepsy by employing a multiscale analysis of intracranial EEG data. The approach integrates entropy and complexity quantification using the Bandt–Pompe method <span>((H times C)</span> plane) with topological feature extraction via Self-Organizing Maps (SOMs) and Uniform Manifold Approximation and Projection (UMAP). Although the entropy-complexity framework captured subject-specific neural characteristics, it did not succeed in distinguishing between preictal and interictal states. In contrast, the SOM-UMAP pipeline revealed clear preictal markers, attributed to the reconfiguration of the mesoscale network using optimal parameters <span>((sigma = 4.0,)</span> <span>(eta = 2.0).)</span> The main contributions of this study include the topological differentiation of brain states beyond the reach of traditional methods, the discovery of individualized epileptogenic patterns in UMAP embeddings, and the development of a validated methodology suitable for implantable device applications. By combining ordinal pattern analysis with topological preservation techniques, this work advances both the theoretical understanding of seizure mechanisms and the practical implementation of personalized seizure prediction tools, outperforming conventional univariate strategies to detect latent preictal signatures.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145406222","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":"First-principles insights into band gap engineering and thermophysical properties of La-based perovskite oxides for solar-driven water splitting","authors":"Wahidullah Khan,&nbsp;Rania Charif,&nbsp;Rachid Makhloufi,&nbsp;Aymen Terki,&nbsp;M. Khasif Masood","doi":"10.1140/epjb/s10051-025-01070-6","DOIUrl":"10.1140/epjb/s10051-025-01070-6","url":null,"abstract":"<div><p>Meeting the global energy demand sustainably has established photocatalysis as a promising route for solar-driven hydrogen production. However, achieving large-scale hydrogen generation through this approach requires materials that are cost-effective, efficient, and stable enough to drive the water-splitting reaction. In this work, we computationally investigate bulk LaZO₃ perovskite oxides for photocatalytic application. The DFT-based calculated indirect band gaps (1.38–2.98 eV) exhibit conduction and valence band edges well aligned to overlap the water redox potentials, indicating suitability for photocatalytic water splitting. Furthermore, the effective mass analysis reveals favorable electron–hole mobility ratios (<i>D</i> = 1.19–4.73), suggesting efficient charge transport and reduced carrier recombination. Furthermore, the lower lattice thermal conductivity of LaZO₃ enhances charge separation and carrier lifetime, thereby improving its overall photocatalytic efficiency. This study establishes non-transition cations in La-based perovskite oxides as sustainable alternatives for solar water splitting.</p><h3>Graphic 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 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145406282","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":"Distributed dynamic strain measurement based on Rayleigh scattering distributed fiber and embedded strain gauge for a NbTi superconducting dipole magnet","authors":"Yongjie Zhang,&nbsp;Zhengnan Han,&nbsp;Canjie Xin,&nbsp;Shijun Zheng,&nbsp;Yu Liang,&nbsp;Teng Tan,&nbsp;Mingzhi Guan","doi":"10.1140/epjb/s10051-025-01075-1","DOIUrl":"10.1140/epjb/s10051-025-01075-1","url":null,"abstract":"<div><p>A NbTi superconducting dipole magnet was recently developed at the Institute of Modern Physics, Chinese Academy of Sciences, as a prototype coil for an advanced high-field facility. To assess its structural stability and performance throughout the whole operation process, both distributed optical fibers and embedded strain gauges were employed to monitor dynamic global strain distribution. The combination of embedded strain gauges and distributed optical fiber sensing technology provides a multi-dimensional, high-precision measurement method for the health detection of superconducting magnets. Both the global and single-point strains of the magnet system were monitored throughout the operating process, including the cooling and excitation phases. This combined approach establishes a layered monitoring pattern including specific point and distributed strain, facilitating a direct assessment of the overall uniformity of the coil structure and essential support for researching the design and electromagnetic characteristics of superconducting magnets.</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 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145406281","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":"Theoretical discovery of the large magnetocrystalline anisotropy in cobalt and manganese silicides, germanides","authors":"Ze Jin Yang","doi":"10.1140/epjb/s10051-025-01069-z","DOIUrl":"10.1140/epjb/s10051-025-01069-z","url":null,"abstract":"<div><p>We searched cobalt and manganese silicides, germanide by crystal structure prediction method and ab initio theory. Five Co₃Si structures presenting lower energies than that of experimental<i> P</i>6₃<i>/mmc</i> are found, including one structure <i>Cmcm</i> that is 60 meV/atom lower than the correspondent <i>P</i>6₃<i>/mmc</i>. A lower-energy Co <span>({text{R}}overline{3} m)</span> (− 7.03 eV/atom) is found, whose energy is higher than that of <i>P</i>6₃<i>/mmc</i> (− 7.04 eV/atom) but is lower than that of <span>({text{F}}moverline{3} m)</span> (− 7.02 eV/atom). Three lower-energy Fe₅Si₃ structures are found, with energies of 30 meV/atom lower than that of experimental <i>P</i>6₃/<i>mcm</i>. The strong lattice shape dependence of magnetocrystalline anisotropy energy (MAE) is studied through X₅Si₃ (X = Mn, Fe, Co). The building-block shape and energy order of cobalt silicide is dominated by Co <i>P</i>6₃<i>/mmc</i>, <span>({text{F}}moverline{3} m)</span>, <span>({text{R}}overline{3} m)</span>, respectively. Several low-energy perfect or nearly-perfect easy-axis MAE for Mn₃Si, Mn₅Si₂, and Mn₅Si₃ structures are found, as are also the cases in Ge-containing counterparts. A structure<i> I</i>4₁22 with energy 300 meV/atom lower than that of experimental Mn₅Si₃ <i>P</i>6₃<i>/mcm</i> is found. One structure Mn₅Si₂ <i>Cmc</i>2₁ with giant MAE is found (<i>E</i>₀₀₁ = 728 and <i>E</i>₁₀₀ = 696 μeV/atom).</p><h3>Graphical abstract</h3><p>We searched binary cobalt silicides by structural prediction code. Five lower-energy structures with lower energies than that of metastable Co₃Si <i>P</i>6₃/<i>mmc</i> are searched, including a structure <i>Cmcm</i> with 60 meV/atom lower than that of <i>P</i>6₃<i>/mmc</i>. A lower-energy Co phase is predicted, <span>({text{R}}overline{3} m)</span> (− 7.03 eV/atom), whose energy is higher than that of <i>P</i>6₃<i>/mmc</i> (− 7.04 eV/atom) but is lower than that of <span>({text{F}}moverline{3} m)</span> (− 7.02 eV/atom).\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 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145406145","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":"Quantum annealing in SK model employing Suzuki–Kubo–deGennes quantum Ising mean field dynamics","authors":"Soumyaditya Das,&nbsp;Soumyajyoti Biswas,&nbsp;Bikas K. Chakrabarti","doi":"10.1140/epjb/s10051-025-01073-3","DOIUrl":"10.1140/epjb/s10051-025-01073-3","url":null,"abstract":"<p>We study a quantum annealing approach for estimating the ground state energy of the Sherrington–Kirpatrick mean field spin glass model using the Suzuki–Kubo–deGennes dynamics applied for individual local magnetization components. The solutions of the coupled differential equations, in discretized state, give a fast annealing algorithm (cost <span>(N^3)</span>) in estimating the ground state of the model: classical (<span>(E^0= -0.7629 pm 0.0002)</span>), quantum (<span>(E^0=-0.7623 pm 0.0001)</span>), and mixed (<span>(E^0=-0.7626 pm 0.0001)</span>), all of which are to be compared with the best known estimate <span>(E^0= -0.763166726 dots )</span> . We infer that the continuous nature of the magnetization variable used in the dynamics here is the reason for reaching close to the ground state quickly and also the reason for not observing the de-Almeida–Thouless line in this approach.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145406143","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":"Metastability in the diluted parallel Ising model","authors":"Franco Bagnoli,&nbsp;Tommaso Matteuzzi","doi":"10.1140/epjb/s10051-025-01064-4","DOIUrl":"10.1140/epjb/s10051-025-01064-4","url":null,"abstract":"<p>We present some considerations about the parallel implementations of the kinetic (Monte Carlo) version of the Ising model. In some cases, the equilibrium distribution of the parallel version does not present the symmetry breaking phenomenon in the low-temperature phase, i.e., the stochastic trajectory originated by the Monte Carlo simulation can jump between the distributions corresponding to both kinds of magnetization, or the lattice can break into two disjoint sublattices, each of which goes into a different asymptotic distribution (phase). In this latter case, by introducing a small asynchronism (dilution), we can have a transition between the homogeneous and the checkerboard phases, with metastable transients.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjb/s10051-025-01064-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145406131","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}

{"title":"Extracting equilibrium information from the non-equilibrium phenomena of sparsely placed water molecules undergoing a finite-time cyclic process","authors":"Yigermal Bassie,&nbsp;Mohammed Mahmud,&nbsp;André Kazuo Takahata,&nbsp;Mulugeta Bekele","doi":"10.1140/epjb/s10051-025-01072-4","DOIUrl":"10.1140/epjb/s10051-025-01072-4","url":null,"abstract":"<p>In this work, we consider a large number of water molecules placed on a lattice far apart, so that they are very weakly interacting with each other and are in contact with a heat bath at temperature <i>T</i>. A strong static electric field, <span>(E_{0})</span>, is applied to these molecules along the <i>z</i>-axis, causing a three-level energy splitting. A weak alternating electric field, applied in the <span>(xy-)</span>plane for a finite-time <span>(tau )</span>, induces transitions between these three levels. This weak alternating field acts as a time-dependent protocol <span>(zeta (t))</span>, which is switched on at <span>(t=0)</span> and off at <span>(t=tau )</span>. The same cyclic process is repeated for a large number of times. The data available for this finite-time non-equilibrium process allow us to extract equilibrium thermodynamic quantities, such as the difference in free energy between the final and initial states of the system. We analytically obtain the work distributions and analyze the average work of the three-level system as a function of <span>(omega )</span> and time around the optimum frequency, where <span>(omega )</span> is the frequency of the alternating electric field. Furthermore, our theoretical framework is further validated through Monte Carlo simulations, which confirm the fidelity of extracting equilibrium free-energy differences and the consistency with the Jarzynski equality.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145405783","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}