物理最新文献

{"title":"Tunable-induced transparency and fast–slow light from atomic ensemble and a yttrium-iron-garnet sphere coupled to microwave cavities","authors":"Qing-hong Liao,&nbsp;Yi-ping Cheng,&nbsp;Shao-cong Deng,&nbsp;Run-zhi Yu","doi":"10.1140/epjp/s13360-025-06910-z","DOIUrl":"10.1140/epjp/s13360-025-06910-z","url":null,"abstract":"<div><p>We theoretically investigate a hybrid cavity magnomechanical system with an atomic ensemble. The atomic ensemble is placed in the intersection of two microwave cavities, and a YIG sphere is located at a microwave cavity driven by a weak probe field. The results show that the phenomena of transparency, absorption and amplification windows can be achieved by adjusting the optomechanical interaction between the cavity and atomic ensemble. The microwave photon–atom coupling strength is found to be linearly correlated with the distance of the absorption peaks through measurement. We also found that better transparency can be gained by properly reducing the decay rate of the cavity and atomic ensemble. Further, we explore the group delay of the output field and find that the system enables fast and slow light conversion. Finally, we discover that atomic ensembles contribute to the modulation of the fast and slow light effects and frequency positions. This scheme has potential value in quantum information storage and high-precision measurements.</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":"145316582","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":"Investigation of radio-frequency sheath structure in electronegative plasma with Cairns–Tsallis electron distribution","authors":"Mohamed Bouzraa,&nbsp;Abdelhak Missaoui,&nbsp;Morad El Kaouini,&nbsp;Mohamed El Bojaddaini,&nbsp;Hassan Chatei","doi":"10.1140/epjd/s10053-025-01076-w","DOIUrl":"10.1140/epjd/s10053-025-01076-w","url":null,"abstract":"<div><p>This study investigates the behavior of a radio-frequency (RF) plasma sheath comprising electrons, positive ions, and negative ions. The sheath structure is analyzed numerically using a one-dimensional hydrodynamic model coupled to an equivalent circuit. In this model, electrons are described by a Cairns–Tsallis distribution, which accounts for both non-extensive and non-thermal characteristics. Positive ions are modeled as a fluid, while negative ions follow a Boltzmann distribution. An equivalent circuit, consisting of a diode, a capacitor, and a current source connected in parallel, is used to describe the spatio-temporal evolution of the RF sheath properties. The results show that as the electronegativity parameter decreases, the sheath structure becomes significantly influenced by the non-extensivity parameter, the non-thermality parameter, the current amplitude, the electron to negative ion temperature ratio, and the current frequency.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"79 10","pages":""},"PeriodicalIF":1.5,"publicationDate":"2025-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316292","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":"Hierarchical WO3 nanostructures via hydrothermal strategy: optical bandgap tuning and high-rate electrochemical response for next-generation supercapacitors","authors":"K. Sphoorthi,&nbsp;A. P. Nagendra Babu,&nbsp;C. G. Renuka","doi":"10.1140/epjp/s13360-025-06963-0","DOIUrl":"10.1140/epjp/s13360-025-06963-0","url":null,"abstract":"<div><p>Hexagonal tungsten trioxide (h-WO₃) is a noteworthy electrode material because of its tunnel-like lattice, multivalent tungsten states, and defect-mediated redox chemistry. This paper identifies hydrothermal duration as a significant factor in determining phase purity, oxygen vacancy density, and crystallite coherence, which directly influences electrochemical performance. By varying the synthesis time systematically (12–72 h), we discover a transition from disordered nanosheets (W12) to hierarchically organized nanosheet nanorod frameworks (W72), the latter of which displays optimal W⁶⁺/W⁵⁺ ratios, effective defect management, and improved electron–phonon coupling (16.6 eV). These enhancements from atomic to mesoscale are reflected in the performance metrics: the W72 electrode delivers 473.45 F g⁻¹ at 1 A g⁻¹, retaining 160.34 F g⁻¹ at 3 A g⁻¹, with minimal charge-transfer resistance (R_ct = 4.99 Ω) and low series resistance (R_s = 0.319 Ω). The asymmetric configuration (W72//AC) achieves an energy density of 15.3 Wh k g⁻¹ and a power density of 2461.5 W k g⁻¹, sustaining 82.3% capacitance retention after 1000 cycles and a quick relaxation time (τ = 0.602 s). This work demonstrates that hydrothermal time-engineering is a robust method for optimizing defects and crystallinity, positioning h-WO₃ as a scalable platform for high-rate, environmentally sustainable supercapacitors and hybrid energy storage systems.</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":"145316581","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":"Effects of QCD-based equation of state on properties of compact stars in gravity’s rainbow","authors":"Ayan Banerjee,&nbsp;Baiju Dayanandan,&nbsp;Javlon Rayimbaev,&nbsp;Sardor Murodov,&nbsp;Inomjon Ibragimov,&nbsp;Sokhibjan Muminov,&nbsp;Ikram Davletov","doi":"10.1140/epjc/s10052-025-14918-z","DOIUrl":"10.1140/epjc/s10052-025-14918-z","url":null,"abstract":"<div><p>In this work, we study the structural and dynamical properties of compact stars using a QCD-motivated equation of state (EoS) within the framework of Gravity’s Rainbow. This theory was proposed as a way to bridge the gap between general relativity and quantum mechanics. Utilizing the modified Tolman–Oppenheimer–Volkoff (TOV) equations, this study examines the impact of energy-dependent spacetime metrics, inspired by doubly special relativity, on the equilibrium configurations of compact stars, particularly those composed of deconfined quark matter. Particularly, we focus on the important consequences arising from applying strong interaction effects, color superconductivity, and the presence of a finite density jump across the quark-hadron interface in the equation of state. In a systematic approach, we investigate the mass-radius relations and compactness of stars, showing the impact of the rainbow on the maximum stable mass and radii of QSs. Notably, the resulting mass-radius relations are well-supported by recent high-precision astrophysical observations, such as the NICER measurement of PSR J0740+6620 and gravitational wave observations (e.g., GW170817). Estimates further confirm these models within observational bounds, while dynamical stability analysis ensures that these configurations are dynamically stable in a large parameter space. Based on these findings, we conclude that quark stars in Gravity’s Rainbow are compact object solutions with viability, as well as provide new avenues in terms of interplay between exotic matter, modified gravity, and observable astrophysical effects.\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/s10052-025-14918-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316241","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":"A memristive hyperchaotic map with extreme multistability: dynamics, complexity, and application in image encryption","authors":"Haneche Nabil,&nbsp;Hamaizia Tayeb","doi":"10.1140/epjp/s13360-025-06953-2","DOIUrl":"10.1140/epjp/s13360-025-06953-2","url":null,"abstract":"<div><p>The memristor’s capacity to change its resistive state in response to external stimuli allows it to serve as the foundation for generating pseudorandom sequences via appropriate control circuitry. Capitalizing on this property, we present a three-dimensional memristive hyperchaotic map (3D-MHM), formulated by merging a sinusoidal nonlinearity with a discrete memristor model to amplify chaotic complexity. An investigation of its dynamics through Lyapunov exponents reveals that the 3D-MHM undergoes transitions from periodic states to chaos and hyperchaos. The intricacy of its iterative output is further validated using metrics such as permutation entropy and <span>(C_0)</span> complexity. A distinctive analysis of this system reveals that it can produce coexisting attractors and multistability, where varying the initial conditions leads to attractors appearing at different spatial positions. Furthermore, the offset boosting behavior of the 3D-MHM displays the coexistence of an infinite number of homogeneous attractors boosted by the memristor initial condition. Leveraging these attributes, a novel color image encryption algorithm based on the 3D-MHM is proposed, presenting a more secure scheme for large-volume data encryption. Statistical and cryptographic analyses confirm the significant potential of the keystream produced by the 3D-MHM for cryptographic applications.</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":"145316243","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":"Unveiling the structural evolution and electronic properties of sodium–aluminum alloy clusters","authors":"Kai Wang,&nbsp;Renqi Zhang,&nbsp;Rui Chen,&nbsp;Chaoyong Wang","doi":"10.1140/epjp/s13360-025-06923-8","DOIUrl":"10.1140/epjp/s13360-025-06923-8","url":null,"abstract":"<div><p>This study systematically investigates the geometric structures and electronic properties of Na_<i>n</i>Al_<i>n</i>^<b>−/0</b> (<i>n</i> = 2 − 10) clusters using a hybrid global optimization algorithm and density functional theory calculations. The ground-state structures of anionic Na_<i>n</i>Al_<i>n</i>^<b>−</b> (<i>n</i> = 2–6) were determined by comparing theoretical and experimental photoelectron spectra. The results indicate structural consistency between neutral and anionic clusters for most sizes, except <i>n</i> = 4 and 9. Al atoms tend to form the cluster core while maintaining geometries isomorphic to their free-standing configurations for <i>n</i> = 2–4, whereas Na atoms preferentially occupy surface sites. In all clusters, Na acts as an electron donor and Al as an electron acceptor. Neutral Na₅Al₅ and its analogs AM₅Al₅ (AM = Li, K, Rb, Cs) are identified as superatoms with a distinctive 1S²1P⁶2S²1D¹⁰ electron configuration and exhibit significant aromatic character.</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":"145316244","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":"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}