物理最新文献

{"title":"Roughness exponents of the liquid/vapor/solid contact line on surfaces with dilute random Gaussian defects: numerical study.","authors":"Stanimir Iliev, Nina Pesheva, Pavel Iliev","doi":"10.1140/epje/s10189-025-00486-3","DOIUrl":"https://doi.org/10.1140/epje/s10189-025-00486-3","url":null,"abstract":"<p><p>We study here the roughness exponents of the averaged contact line width of a liquid in contact with flat, weakly heterogeneous substrates containing dilute, randomly distributed Gaussian-type defects. For this purpose, we employ the full capillary model. The obtained results for the magnitude of the averaged root-mean-square width of the contact line show that there is only one interval in which the width scales with length as a power function. The numerical studies and analysis indicate that this interval should be regarded as a length scale smaller than the jog length. The roughness exponent found is not a universal constant independent of the apparent contact angle formed by the liquid on the solid surface. It closely approaches the theoretically predicted value of 1/2 [M. O. Robbins, and J. F. Joanny, Europhys. Lett. 3, 729 (1987)] only within the contact angle ranges of <math><msup><mn>10</mn> <mo>∘</mo></msup> </math> to <math><msup><mn>30</mn> <mo>∘</mo></msup> </math> and <math><msup><mn>150</mn> <mo>∘</mo></msup> </math> to <math><msup><mn>170</mn> <mo>∘</mo></msup> </math> . Furthermore, it can be considered that there is still a significant range of contact angles, from <math><msup><mn>55</mn> <mo>∘</mo></msup> </math> up to <math><msup><mn>125</mn> <mo>∘</mo></msup> </math> , in which the roughness exponent remains practically constant, however, having a value of 0.8.</p>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"48 6-7","pages":"32"},"PeriodicalIF":1.8,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144300929","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":"In vivo assessment of kinematic relationships for epithelial morphogenesis.","authors":"Toshinori Namba, Kaoru Sugimura, Shuji Ishihara","doi":"10.1140/epje/s10189-025-00495-2","DOIUrl":"10.1140/epje/s10189-025-00495-2","url":null,"abstract":"<p><p>Tissue growth and deformation result from the combined effects of various cellular events, including cell shape change, cell rearrangement, cell division, and cell death. Resolving and integrating these cellular events is essential for understanding the coordination of tissue-scale growth and deformation by individual cellular behaviors that are critical for morphogenesis, wound healing, and other collective cellular phenomena. For epithelial tissues composed of tightly connected cells, the texture tensor method provides a unified framework for quantifying tissue and cell strains by tracking individual cells in live imaging data. The corresponding kinematic relationships have been introduced in a hydrodynamic model that we previously reported. In this study, we quantitatively evaluated the kinematic equations proposed in the hydrodynamic model using experimental data from a growing Drosophila wing. To accomplish this, we introduced modified definitions of the texture tensor and confirmed that one of these modifications more accurately represents approximated cellular shapes without relying on ad hoc scaling factors. By utilizing the modified tensor, we demonstrated the compatibility of the strain rate tensors and the accuracy of both the kinematic and cell number density equations. These results cross-validate the modified texture analysis and the hydrodynamic model. Furthermore, the precision of the kinematic relationships achieved in this study provides a robust foundation for more advanced integration of modeling and experiment.</p>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"48 6-7","pages":"31"},"PeriodicalIF":1.8,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144300928","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":"Smart navigation of microswimmers in Poiseuille flow via reinforcement learning.","authors":"Priyam Chakraborty, Rahul Roy, Shubhadeep Mandal","doi":"10.1140/epje/s10189-025-00496-1","DOIUrl":"https://doi.org/10.1140/epje/s10189-025-00496-1","url":null,"abstract":"<p><p>Artificial microswimmers, such as active colloids, have the potential to revolutionize targeted drug delivery, but controlling their motion under imposed flow conditions remains challenging. In this work, we implement reinforcement learning (RL) to control the navigation of a microswimmer in a plane Poiseuille flow, with applications in targeted drug delivery. With RL, the swimmer learns to efficiently reach its target by continuously adjusting its swinging or tumbling behavior depending upon its self-propulsion strength, chirality and the imposed flow strength. This RL-based approach enables precise control of the particle's path, achieving reliable targeting even in stringent scenarios such as upstream motion in high bulk flow, thus advancing the design of intelligent in vivo medical microrobots.</p>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"48 6-7","pages":"30"},"PeriodicalIF":1.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273923","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":"Review: Quantum metrology and sensing with many-body systems","authors":"Victor Montenegro ,&nbsp;Chiranjib Mukhopadhyay ,&nbsp;Rozhin Yousefjani ,&nbsp;Saubhik Sarkar ,&nbsp;Utkarsh Mishra ,&nbsp;Matteo G.A. Paris ,&nbsp;Abolfazl Bayat","doi":"10.1016/j.physrep.2025.05.005","DOIUrl":"10.1016/j.physrep.2025.05.005","url":null,"abstract":"<div><div>Quantum systems, fabricated across various spatial scales from nano to micrometers, are very delicate and naturally sensitive to the variations of their environment. These features make them excellent candidates for serving as sensors with wide range of applications. Indeed, the exceptional precision of quantum sensors arises from their compact size and inherent sensitivity, enabling measurements with unprecedented accuracy within highly localized regions. A key advantage of quantum sensors lies in their resource efficiency, as their achievable precision can scale super-linearly with respect to resources, such as system size, in contrast to the linear scaling characteristic of classical sensors. This phenomenon, commonly referred to as quantum-enhanced sensitivity, fundamentally depends on exploiting uniquely quantum mechanical features, including superposition, entanglement, and squeezing. Originally, quantum sensing was formulated for particles prepared in a special form of entangled states. Yet, certain realization of these probes may be susceptible to decoherence and interaction between particles may also be detrimental to their performance. An alternative framework for quantum sensing has been developed through exploiting quantum many-body systems, where the interaction between particles plays a crucial role. In this review, we investigate different aspects of the latter approach for quantum metrology and sensing. Many-body probes have been used for sensing purposes in both equilibrium and non-equilibrium scenarios. Quantum criticality, as a well-studied subject in many-body physics, has been identified as a resource for achieving quantum-enhanced sensitivity in both of these scenarios. In equilibrium, various types of criticalities, such as first order, second order, topological, and localization phase transitions have been exploited for sensing purposes. In non-equilibrium scenarios, quantum-enhanced sensitivity has been discovered for Floquet, dissipative, and time crystal phase transitions. While each type of these criticalities, either in equilibrium or non-equilibrium scenarios, has its own characteristics, the presence of one feature is crucial for achieving quantum-enhanced sensitivity and that is energy/quasi-energy gap closing. In non-equilibrium quantum sensing, time becomes another parameter which can affect the sensitivity of the probe. Typically, the sensitivity enhances as the probe evolves in time. In this review, we provide an overview on recent progresses on different aspects of quantum metrology and sensing with many-body systems.</div></div>","PeriodicalId":404,"journal":{"name":"Physics Reports","volume":"1134 ","pages":"Pages 1-62"},"PeriodicalIF":23.9,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144223360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Three-dimensional Abelian and non-Abelian gauge Higgs theories","authors":"Claudio Bonati ,&nbsp;Andrea Pelissetto ,&nbsp;Ettore Vicari","doi":"10.1016/j.physrep.2025.05.004","DOIUrl":"10.1016/j.physrep.2025.05.004","url":null,"abstract":"<div><div>Gauge symmetries and Higgs mechanisms are key features of theories describing high-energy particle physics and collective phenomena in statistical and condensed-matter physics. In this review we address the collective behavior of systems of multicomponent scalar fields interacting with gauge fields, which can be already present in the underlying microscopic system or emerge only at criticality. The interplay between local gauge and global symmetries determines the phase diagram, the nature of the Higgs phases, and the nature of phase transitions between the high-temperature disordered and the low-temperature Higgs phases. However, additional crucial features determine the universal properties of the critical behavior at continuous transitions. Specifically, their nature also depends on the role played by the gauge modes at criticality. Effective (Abelian or non-Abelian) gauge Higgs field theories emerge when gauge modes develop critical correlations. On the other hand, a more standard critical behavior, which admits an effective description in terms of Landau–Ginzburg–Wilson <span><math><msup><mrow><mi>Φ</mi></mrow><mrow><mn>4</mn></mrow></msup></math></span> theories, occurs when gauge-field modes are short ranged at the transition. In the latter case, gauge fields only prevent non-gauge invariant correlation functions from becoming critical. This review covers the recent progress made in the study of Higgs systems with Abelian and non-Abelian gauge fields. We discuss the equilibrium thermodynamic properties of systems with a classical partition function, focusing mainly on three-dimensional systems, and only briefly discussing two-dimensional models. However, by using the quantum-to-classical mapping, the results on the critical behavior for classical systems in <span><math><mrow><mi>D</mi><mo>=</mo><mi>d</mi><mo>+</mo><mn>1</mn></mrow></math></span> dimensions can be extended to quantum transitions in <span><math><mi>d</mi></math></span> dimensions.</div></div>","PeriodicalId":404,"journal":{"name":"Physics Reports","volume":"1133 ","pages":"Pages 1-92"},"PeriodicalIF":23.9,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144190402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Effect of Gd-doping on magnetic, ferroelectric, and optical properties of BiFeO3 multiferroic nanoparticles synthesized by Sol-gel route","authors":"Subhasmita Jena,&nbsp;Sovan Kumar Patra,&nbsp;Budhendra Singh,&nbsp;Amiya Priyam,&nbsp;Bhavya Bhushan","doi":"10.1007/s00339-025-08621-9","DOIUrl":"10.1007/s00339-025-08621-9","url":null,"abstract":"<div><p>Multiferroic nnanoparticles (NPs) of pristine BiFeO₃ (BFO) and Gd-doped BFO, Bi_1 − xGd_xFeO₃ (x = 0.01, 0.03, and 0.05) were synthesized by ethylene glycol-based sol-gel route. The impact of Gd-concentration on their structural, optical, ferroelectric, and magnetic characteristics has been examined. XRD confirmed the phase purity and, it was found that the rhombohedral distorted perovskite structure remained the same on Gd-doping. The average particle size, as determined by FE-SEM, decreased exponentially in the following manner, 46 → 44 → 42 → 41 nm for Gd-doping level varying as 0% → 1% → 3% → 5%, respectively. In Raman spectra of 5%-Gd-doped NPs, the phonon modes corresponding to A₁ ^− 3, A₁ ^− 4 and E peaks show a red shift of 2.6 cm^− 1, 2.5 cm^− 1, and 5.2 cm^− 1, respectively. Well-defined absorption peak at 459 nm was seen in UV-visible absorption spectra of BFO NPs which blue-shifted to 446 nm and the bandgap varied linearly with dopant concentration. 3% Gd-doping was found to be optimum as it caused more than 100% enhancement of the saturation and remanent magnetization, upto 0.702 emu/g and 0.057 emu/g, respectively. In ferroelectric measurements, all samples showed non-saturating P-E hysteresis curves, with pristine BFO having the maximum remnant polarization. These Gd-doped BFO NPs with enhanced magnetic and optical properties are well-suited for applications in photocatalysis and spintronics.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140141","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":"The study of the effect of device downsizing on 1/f noise in deep submicron magnetic tunnel junctions","authors":"T. N. Anh Nguyen,&nbsp;Q. N. Pham,&nbsp;K. T. Do,&nbsp;H. K. Vu,&nbsp;H. N. Pham,&nbsp;D. T. Tran,&nbsp;H. M. Do","doi":"10.1007/s00339-025-08630-8","DOIUrl":"10.1007/s00339-025-08630-8","url":null,"abstract":"<div><p>In this study, nanoscale MgO magnetic tunnel junctions (MTJs) with an orthogonal magnetization structure between the free and pinned layers and various junction sizes were fabricated, and their tunnel magnetoresistance (TMR) ratio, resistance-area (RA) product, and low-frequency noise (LFN) behavior were experimentally investigated thoroughly. The circular MTJs with various diameters (80–400 nm) show high TMR ratios of greater than 100% at room temperature (RT) with relatively low RA in the range of 2.8–4.4 Ωµm². We found that the noise power spectral density (PSD) as a function of d.c. bias voltage (<i>V</i>_bias) and perpendicular d.c. bias magnetic field (<i>H</i>_DC) in all junction sizes exhibits 1/<i>f</i>-noise behavior within a wide investigated frequency range from 5 Hz up to 10 kHz. The bias voltage and magnetic field-dependent LFN indicated that the 1/<i>f</i> noise of the MTJs has both electric and magnetic origins. The results show that though the TMR ratio and RA product are size-independent, the Hooge parameter for the parallel (P) state (<i>α</i>_P) is strongly dependent on the MTJ size, and its values decrease with decreasing MTJ size, suggesting the reduction of electronic 1/<i>f</i> noise as the MTJ size shrinks. This is the first experimental report on the size dependency of electronic 1/<i>f</i> noise in nano-sized MTJs. The results may open a new approach for reducing not only magnetic but also electronic 1/<i>f</i> noises in MTJs by downscaling, thereby increasing the sensitivity of MTJ nanosensors.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 6","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140139","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":"Impact of strong magnetic field, baryon chemical potential, and medium anisotropy on polarization and spin alignment of hadrons","authors":"Bhagyarathi Sahoo,&nbsp;Captain R. Singh,&nbsp;Raghunath Sahoo","doi":"10.1140/epjc/s10052-025-14260-4","DOIUrl":"10.1140/epjc/s10052-025-14260-4","url":null,"abstract":"<div><p>The recent observation of global spin polarization of <span>(Lambda )</span> (<span>(bar{Lambda })</span>) hyperons and the spin alignment of <span>(phi )</span> and <span>(K^{*0})</span> vector mesons create remarkable interest in investigating the particle polarization in the relativistic fluid produced in heavy-ion collisions at GeV/TeV energies. Among other sources of spin polarization phenomena, the Debye mass of a medium plays a crucial role in particle polarization. Any modification brought to the effective mass due to the temperature, strong magnetic field (<i>eB</i>), baryonic chemical potential (<span>(mu _{B})</span>), medium anisotropy (<span>(xi )</span>), and vorticity, etc., certainly affects the particle spin polarization. In this work, we explore the global hyperon spin polarization and the spin alignment of vector mesons corresponding to the strong magnetic field, baryonic chemical potential, and medium anisotropy. We find that the degree of spin polarization is flavor-dependent for hyperons. Meanwhile, vector meson spin alignment depends on the hadronization mechanisms of initially polarized quarks and anti-quarks. Medium anisotropy significantly changes the degree of spin polarization compared to the magnetic field and baryon chemical potential.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 5","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14260-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140269","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":"Friedmann–Lemaître universes and their metamorphoses","authors":"Spiros Cotsakis","doi":"10.1140/epjc/s10052-025-14312-9","DOIUrl":"10.1140/epjc/s10052-025-14312-9","url":null,"abstract":"<div><p>We analyze the dynamics of the Friedmann–Lemaître universes taking into account the different roles played by the fluid parameter and the cosmological constant, as well as the degenerate character of the equations. We find that the Friedmann–Lemaître system reduces to four qualitatively inequivalent normal forms and write down the sets of all stable perturbations that may result (the ‘versal unfoldings’). These sets are of small codimension up to three. We then describe all possible parameter-dependent solutions and their transfigurations to other forms during evolution through the bifurcation sets, these are also fully described. This analysis leads to a picture of cosmological evolution determined by new parameters related to codimension which are zero in standard cosmology. The emerging versal solutions are all free of singularities, while other properties of them are also discussed.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 5","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14312-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140270","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 simulation study of electrical conductivity of porous rocks: effect of clay, porosity, temperature and Peclet number.","authors":"Supti Sadhukhan, Tapati Dutta","doi":"10.1140/epje/s10189-025-00494-3","DOIUrl":"10.1140/epje/s10189-025-00494-3","url":null,"abstract":"<p><p>This study investigates the impact of clay content and temperature variation on the electrical conductivity of three-dimensional fluid-filled porous rocks. The role of varying pore throat radii has been included in the course of clay fraction variation in the conducting channels of the rock samples. The research identifies a critical ratio of clay conductance to fluid conductance that dictates the regime of electrical conductance behaviour. A nonlinear increase in electrical conductance is observed when the clay-to-fluid conductance ratio exceeds the critical ratio, whereas a linear relationship is maintained below this critical ratio. A modified form of Archie's law relating effective conductivity and porosity has been proposed for the clay coated channels. The intricate relationship between Peclet number, pore throat size, and temperature on the electrical conductivity of fluid-filled straight channels in three dimensions has also been investigated. Results revealed a quadratic increase in conductance with porosity under steady-state conditions across all Peclet number ranges examined. While the conductivity remained constant with porosity for each Peclet number, the rate of increase in conductivity diminished with it. Nonlinear increase in conductivity was observed with temperature in the transient flow regime with a threshold temperature marking the onset of conductivity. Conductivity was augmented with increase in observation time in the transient state for the entire temperature range considered. Close to the attainment of saturation in electrical conductivity, the conductivity changed linearly with temperature until a steady value was reached.</p>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"48 4-5","pages":"29"},"PeriodicalIF":1.8,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144155488","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}