物理最新文献

{"title":"Dynamical complexities in a food chain model with schooling behavior: a study in a parameter plane","authors":"Subarna Roy,&nbsp;Ruma Kumbhakar,&nbsp;Sarbari Karmakar,&nbsp;Pankaj Kumar Tiwari,&nbsp;Nikhil Pal","doi":"10.1140/epjp/s13360-025-06939-0","DOIUrl":"10.1140/epjp/s13360-025-06939-0","url":null,"abstract":"<div><p>The food chain provides crucial insights into the intricate interdependencies within ecosystems, guiding effective conservation and management strategies. The primary goal of this study is to investigate the dynamical complexities of a deterministic tri-trophic food chain model where the interaction between the prey and the middle predator is described using the Holling type-II response function, whereas Cosner functional response is used to describe the interaction between the middle and top predators. Bifurcation, Lyapunov exponent, and isospike diagrams reveal various kinds of dynamical behaviors of the system. Shrimp-shaped and spiral shrimp-shaped domains are observed in the chaotic zone of the parameter plane. The coexistence of various types of attractors and spike-bubbling phenomenon are also observed. The corresponding stochastic model is also studied in the presence of environmental noise. This study offers valuable information about the persistence and conservation of species in both deterministic and stochastic environments.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"On energy–momentum tensor for gravitational waves in f(R) gravity","authors":"Petr V. Tretyakov,&nbsp;Alexander N. Petrov","doi":"10.1140/epjc/s10052-025-14901-8","DOIUrl":"10.1140/epjc/s10052-025-14901-8","url":null,"abstract":"<div><p>The classical Isaacson’s procedure for describing back-reaction of the averaged energy–momentum for high frequency gravitational waves is generalized to the <i>f</i>(<i>R</i>) gravity case. From the beginning it is assumed that an initial background could be arbitrary one. Then, we restrict the background to be de Sitter, which is a novelty regarding the study of a back-reaction in <i>f</i>(<i>R</i>) gravity. Consideration of the de Sitter space as a background spacetime allows us to provide the averaging procedure completely. Using the results on the de Sitter space and generalizing the Isaacson procedure, we construct the averaged energy–momentum on an additionally curved (averaged) background. Consistency tests for de Sitter spacetime are performed both at the background and perturbative regimes. Our results generalize previous studies in which the authors consider the flat (Minkowski) spacetime as the initial background.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14901-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"The (eta ^prime N) interaction from the (eta ^prime p) correlation function","authors":"Natsumi Ikeno","doi":"10.1140/epja/s10050-025-01716-0","DOIUrl":"10.1140/epja/s10050-025-01716-0","url":null,"abstract":"<div><p>We evaluate for the first time the <span>(eta ^prime p)</span> femtoscopic correlation function to study the <span>(eta ^prime N)</span> interaction. We find it extremely sensitive to the value of the <span>(eta ^prime p)</span> scattering length, for which at present there exists only very limited information, not even knowing its sign. The measurement of this correlation function would provide much valuable information on the <span>(eta ^prime N)</span> interaction, which could then also be used to settle the issue of possible <span>(eta ^prime )</span> nucleus bound states, an issue attracting much attention in the nuclear physics community.</p></div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 10","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Enhanced energy storage via one-step preparation of Cuo-nanosalt","authors":"Afrah Turki Awad,&nbsp;Mustafa Naozad Taifor,&nbsp;Abdulelah Hameed Yaseen,&nbsp;Uday M. Nayef,&nbsp;Tareq H. Abeda,&nbsp;Mohammed W. Muayad,&nbsp;Dongsheng Wen","doi":"10.1140/epjp/s13360-025-06924-7","DOIUrl":"10.1140/epjp/s13360-025-06924-7","url":null,"abstract":"<div><p>Molten salts are widely used as thermal energy storage materials in solar thermal systems; however, their limited thermophysical properties, particularly low specific heat capacity, restrict their performance. This study uses a novel one-step method to prepare nanoparticles directly in the base salt under different preparation conditions. We have extended the examination of various preparation conditions from our previous study. The precursor material was copper sulfate uses to produce copper oxide (CuO) nanoparticles. The concentrations of the prepared CuO nanoparticles keeps fixed at 1 wt.%. The preparation processes of CuO nanoparticles were at different times and temperatures. The results reveal a significant influence of the preparation method conditions on the enhancement of thermophysical properties of nanosalt. The one-step method achieved the highest increase in specific heat capacity, with improvements of 32.63% in the solid phase and 21.74% in the liquid phase compared to the base salt without any additives. Additionally, sensible heat storage improved by 8.623% using the one-step nanosalt formulation. More notably, latent heat showed a remarkable increase of 76.46% for the one-step CuO-nanosalt compared to the pure binary salt. Furthermore, the one-step method is a cost-effective way to save on the cost and time of preparations by 89.27%. These findings underscore the crucial role of the preparation technique in determining the thermal behavior of nanosalts. Transmission electron microscopy (TEM) analysis confirmed the presence of CuO nanoparticle agglomeration in samples prepared via the one-step method, which may contribute to the observed enhancements. This work provides new insights into optimizing nanosalt formulations for more efficient thermal energy storage systems.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"An iterative solving framework for local fine space of balancing domain decomposition","authors":"Shijie Huang,&nbsp;Yuhui Chen,&nbsp;Qinghe Yao","doi":"10.1140/epjp/s13360-025-06932-7","DOIUrl":"10.1140/epjp/s13360-025-06932-7","url":null,"abstract":"<div><p>In this paper, we propose an improved balancing domain decomposition (BDD) method, developed within an iterative solving framework, for large-scale symmetric positive-definite sparse systems. Traditional BDD-NN approaches, which combine Neumann–Neumann (NN) preconditioners with direct solvers for local fine space problems, encounter computational limitations due to the singularity of their coefficient matrix. To address this limitation, we introduce a regularization technique and replace direct solvers with iterative alternatives. Two categories of iterative methods—matrix splitting techniques, such as Gauss Seidel (GS) and Successive Over Relaxation (SOR), and Krylov subspace methods, including the Full Orthogonalization Method (FOM), Generalized Minimum Residual (GMRES), and Minimum Residual Method (MINRES)—are incorporated into the BDD framework to solve local fine space problems effectively. We systematically formulate the resulting BDD-GS, BDD-SOR, BDD-FOM, BDD-GMRES, and BDD-MINRES methods and theoretically establish the convergence of the corrected local problems for these proposed iterative strategies. We evaluate performance using 10 nodes, each with 64 processors, focusing on linear systems derived from the Poisson equation. Experimental results show that the proposed BDD-type iterative methods achieve enhanced parallel scalability, maintain numerical scalability, and reduce computational time compared to the conventional BDD-NN for large-scale Schur complement systems. These results confirm the effectiveness of iterative BDD variants in addressing large-scale problems.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Particle–hole transport in a TBCCO superconducting single-channel NSNSNSN nanowire","authors":"F. Estrella,&nbsp;L. E. Reichl","doi":"10.1140/epjp/s13360-025-06957-y","DOIUrl":"10.1140/epjp/s13360-025-06957-y","url":null,"abstract":"<div><p>High-temperature superconductors open new avenues for developing nanoscale superconducting circuits with potential applications in quantum information processing. In this study, we focus on the characterization of single-channel ballistic electron wave propagation in composite NSNSNSN nanowires using the high <span>(T_c)</span> superconductor TBCCO (<span>(text {Tl}_2text {Ba}_2text {Ca}_2text {Cu}_3text {O}_{10+delta })</span>). These nanowires are designed to preserve the coherence of a superconducting state while maintaining the simplicity of a quasi-one-dimensional system. Our analysis determines the geometric and thermal conditions to build such nanowires. By examining the scattering matrix, we identify conditions under which quasi-bound states significantly influence the transmission and reflection amplitudes, thereby affecting particle and hole propagation. Furthermore, we explore the nearly ergodic scattering behavior at resonant energies, where the scattering system exhibits nearly equal probability for the various scattering outcomes.\u0000</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Influence of structural defects on the spectral characteristics of Er3+ impurities in Y2SiO5 crystals","authors":"I. Nuritdinov,&nbsp;Z. U. Esanov,&nbsp;Kh. M. Majidov,&nbsp;F. K. Khallokov,&nbsp;N. M. Kilichov","doi":"10.1140/epjb/s10051-025-01068-0","DOIUrl":"10.1140/epjb/s10051-025-01068-0","url":null,"abstract":"<div><p>This study investigates the influence of gamma irradiation (up to 10⁸ rad) and subsequent thermal annealing (700 °C, up to 9 h) on the spectral characteristics of Y₂SiO₅:Er³⁺ crystals. It has been established that these treatments induce the formation of oxygen vacancies in the crystal, leading to coordination transformations from Er1 to Er2 sites. This is accompanied by a redistribution of the intensities of f–f transitions, which enabled the spectroscopic identification and differentiation of two types of Er³⁺ centers with distinct coordination environments. Induced absorption and luminescence bands associated with the formation of F and F⁺ centers were observed. It was demonstrated that changes in the local crystal field surrounding the Er³⁺ ions lead to noticeable Stark splitting, as evident in both absorption and photoluminescence spectra. The results demonstrate the potential for controlled modification of the material’s optical properties via coordination rearrangement, which is of interest for photonic and quantum technologies.</p><h3>Graphic 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 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316507","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":"A cryogenic Paul trap for probing the nuclear isomeric excited state (^{229text {m}})Th(^{3+})","authors":"Daniel Moritz,&nbsp;Kevin Scharl,&nbsp;Markus Wiesinger,&nbsp;Georg Holthoff,&nbsp;Tamila Teschler,&nbsp;Mahmood I. Hussain,&nbsp;José R. Crespo López-Urrutia,&nbsp;Timo Dickel,&nbsp;Shiqian Ding,&nbsp;Christoph E. Düllmann,&nbsp;Eric R. Hudson,&nbsp;Sandro Kraemer,&nbsp;Lilli Löbell,&nbsp;Christoph Mokry,&nbsp;Jörg Runke,&nbsp;Benedict Seiferle,&nbsp;Lars von der Wense,&nbsp;Florian Zacherl,&nbsp;Peter G. Thirolf","doi":"10.1140/epjd/s10053-025-01071-1","DOIUrl":"10.1140/epjd/s10053-025-01071-1","url":null,"abstract":"<p>While laser excitation of the nuclear isomeric transition in <span>(^{229})</span>Th has been recently achieved for thorium atoms embedded in large-bandgap crystals, laser excitation and characterization of the nuclear transition in trapped <span>(^{229})</span>Th<span>(^{3+})</span> ions has not yet been accomplished. To address these experiments, a cryogenic Paul trap setup has been designed, built, and commissioned at LMU Munich. Here, we present the specifications of the new experimental platform and demonstrate its successful operation, showing the extraction, subsequent ion guiding, mass purification, and trapping of <span>(^{229})</span>Th<span>(^{3+})</span> and <span>(^{229text {m}})</span>Th<span>(^{3+})</span> ions from a newly designed buffer-gas stopping cell as well as of <span>(^{88})</span>Sr<span>(^{+})</span> ions from laser ablation of a solid target. Further, we show sympathetic laser cooling of <span>(^{229text {(m)}})</span>Th<span>(^{3+})</span> by Doppler-cooled <span>(^{88})</span>Sr<span>(^{+})</span> ions and the formation of mixed-species Coulomb crystals.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"79 10","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-025-01071-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316520","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":"Thermoelastic damping analysis to CNTs and GPLs reinforced FG microplate based on nonlocal strain gradient theory and nonlocal dual-phase-lag heat conduction model","authors":"Weixuan Wang,&nbsp;Tianhu He","doi":"10.1007/s00339-025-08987-w","DOIUrl":"10.1007/s00339-025-08987-w","url":null,"abstract":"<div><p>This study aims to investigate the thermoelastic damping (TED) mechanism of functionally graded (FG) microplates reinforced by graphene platelets (GPLs) and carbon nanotubes (CNTs), addresses the failure of the classical TED model at the microscale, and fills the existing gaps in TED research concerning FG-GPLs/CNTs reinforced microstructures. By integrating the nonlocal strain gradient theory (NSGT) and the nonlocal dual-phase-lag (NDPL) heat conduction model into the Kirchhoff plate theory, a novel comprehensive model that captures spatiotemporal nonlocal effects is derived. The complex frequency method is employed to solve the model, with the effective elastic modulus evaluated by the Halpin–Tsai micromechanical model. The study examines the influence of several key variables on TED across four distribution patterns, i.e., UD type, FG-A type, FG-O type, and FG-X type. The results indicate that the normalized inverse quality factor peaks at the highest value in the FG-X type, reaching 0.96 at 1.96 μm. In contrast, the FG-A type exhibits superior overall damping performance. The elastic nonlocal parameter extends the TED range in the thickness direction, with the peak position shifting approximately 0.2 μm toward the top of the microplate for every 50 nm increase. However, the characteristic length parameter narrows this range. The nonlocal thermal effects diminish energy dissipation. Crucially, GPLs are the primary determinants of TED; an increase in their mass fraction leads to a reduction in peak and an expansion of the dissipation area, while geometric parameters exhibit a negligible influence. Conversely, CNTs solely modify spatial dissipation distribution through mass fraction without affecting the peak values, whereas increased geometric thickness induces strain gradients. Furthermore, TED demonstrates maximum strength under SSSS boundary conditions. The current model and results offer valuable insights for the design of high-performance FG advanced MEMS reinforced by GPLs and CNTs.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 11","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasma sheath physics: a circuital description, amelioration, and application","authors":"Pralay Kumar Karmakar,&nbsp;Subham Dutta,&nbsp;Utpal Deka","doi":"10.1140/epjp/s13360-025-06928-3","DOIUrl":"10.1140/epjp/s13360-025-06928-3","url":null,"abstract":"<div><p>A synoptic review of the electrical circuital model-based analysis of laboratory plasma sheaths, alongside their stability features in a realistic broader horizon, is systematically presented herein. It explains the basic physics responsible behind the inductive (<span>(L_{sh})</span>), capacitive (<span>(C_{sh})</span>), and resistive (<span>(R_{sh})</span>) properties simultaneously, exhibited by plasma sheaths. The analyzed model sheath behaviors are judiciously described in the light of the state-of-the-art sheath scenarios illustratively. The sheath-based circuital components are minutely contrasted with the commercially available circuital counterparts. The applications of the novel circuital sheath model in widespread fields of research having both fundamental and applied importance are discussed. The main merits of modeling plasma sheaths through the circuital formalism over the existing non-circuital theoretic ones are outlined together with future scope.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><img></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 10","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}