The European Physical Journal Plus最新文献_第8页

Oscillation suppression and revival in time-delayed chaotic oscillators via delayed mean-field feedback: theory and experiment 延迟平均场反馈的时滞混沌振荡抑制与恢复：理论与实验

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-25 DOI: 10.1140/epjp/s13360-026-08335-8

Tapas Mandal, Debabrata Biswas

{"title":"Oscillation suppression and revival in time-delayed chaotic oscillators via delayed mean-field feedback: theory and experiment","authors":"Tapas Mandal, Debabrata Biswas","doi":"10.1140/epjp/s13360-026-08335-8","DOIUrl":"10.1140/epjp/s13360-026-08335-8","url":null,"abstract":"<div><p>Time delay is a fundamental feature of many natural and engineered systems. It often governs the collective behavior of interacting dynamical units. Here, we study chaotic oscillators with intrinsic time delay, coupled through delayed mean-field feedback. We aim to understand how this coupling delay, introduced due to finite transmission time in the coupling channel, influences oscillation suppression and its subsequent recovery. Analytical and numerical results reveal several collective dynamical states, including chaotic oscillations, inhomogeneous limit cycles, amplitude death, nontrivial amplitude death, and oscillation death (OD). Their transitions are identified through linear stability analysis to a certain extent, bifurcation analysis, and the master stability function. We show that delayed mean-field feedback can drive the system to OD. The same mechanism can also recover oscillatory dynamics from suppressed states by suitably adjusting the coupling delay. We find the basin of attraction for the coexisting multistable states arising in the coupled system. Electronic circuit experiments support the theoretical and numerical predictions and show close qualitative agreement. The robustness of the proposed mechanism is further verified in large oscillator networks and in the Ikeda time-delay system. These results demonstrate that delayed mean-field feedback provides an effective route for regulating oscillation suppression and rhythm generation in complex time-delayed networks, with potential relevance to physical, biological, and engineering systems.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149034980","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}

引用次数: 0

Energy, passivity, and diffusive representations in anisotropic fractional Maxwell–Cole–Cole media 各向异性分数麦克斯韦-科尔-科尔介质中的能量、被动性和扩散表征

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-25 DOI: 10.1140/epjp/s13360-026-08338-5

Nikko John Leo S. Lobos

{"title":"Energy, passivity, and diffusive representations in anisotropic fractional Maxwell–Cole–Cole media","authors":"Nikko John Leo S. Lobos","doi":"10.1140/epjp/s13360-026-08338-5","DOIUrl":"10.1140/epjp/s13360-026-08338-5","url":null,"abstract":"<div><p>This study develops an energy formulation for linear anisotropic Maxwell–Cole–Cole media with multiple fractional polarization channels, passive conductivity, prescribed external currents, and finite-terminal Caputo memory with zero prehistory. A weighted temporal solution class admits the integrable fractional initial layer generated by quiescent polarization data. The fractional polarization power separates into a non-negative history-storage functional and a non-negative constitutive dissipation rate. The instantaneous dissipation may diverge at initialization but remains integrable, while the stored history energy and accumulated loss vanish initially. Combining this decomposition with the Poynting theorem gives a global field-plus-memory energy identity, electromagnetic passivity, closed-system energy decay, and conditional uniqueness under boundary conditions with zero supply. The analysis also recovers the Debye, instantaneous-dielectric, vanishing-susceptibility, and vacuum limits under stated convergence and compatibility assumptions. A positive diffusive representation gives a second admissible energy decomposition. Its storage does not exceed the history storage. Their difference is an exact non-negative weighted variance that vanishes only for a zero polarization history. The long-time limit of the finite-time harmonic response gives the anisotropic multichannel Cole–Cole permittivity, whose Hermitian imaginary part yields non-negative cycle-averaged absorption. A reproducible single-channel parameter study shows how the fractional order broadens the dielectric-loss band, redistributes wave attenuation, strengthens the integrable initial power layer, and lengthens the step-response tail. An exact electric-step response checks both energy representations. The resulting formulation relates the fractional initial layer, hereditary storage, passivity, diffusive relaxation, dispersion, absorption, and attenuation in a spatially local constitutive model.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149034998","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}

引用次数: 0

Design, synthesis, structure and property of the nonlinear optical material Ta-doped MnTeMoO6 掺ta非线性光学材料MnTeMoO6的设计、合成、结构与性能

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08334-9

Chengguo Jin

{"title":"Design, synthesis, structure and property of the nonlinear optical material Ta-doped MnTeMoO6","authors":"Chengguo Jin","doi":"10.1140/epjp/s13360-026-08334-9","DOIUrl":"10.1140/epjp/s13360-026-08334-9","url":null,"abstract":"<div><p>Because of the second-order nonlinear optical behavior, MnTeMoO<sub>6</sub> crystals have a possible application in the field of optical parameter amplification and laser frequency conversion. To improve the performance of MnTeMoO<sub>6</sub>, Ta-doped MnTeMoO<sub>6</sub> (Ta:MnTeMoO<sub>6</sub>) structures have been designed, and calculated via the first-principles method. On the basis of the prediction from the theoretical calculations, the Mo-substituted structure of Ta:MnTeMoO<sub>6</sub> was selected, and the resultants with Ta-addition ratio at 1 ~ 8 mol% have been synthesized. The experimental results reveal that the actual doping ratios are less than 2 mol% in the Ta:MnTeMoO<sub>6</sub> resultants with a single crystalline phase. Ta:MnTeMoO<sub>6</sub> resultants with Ta-addition ratio at 1 ~ 2 mol% exhibit a higher band-gap energy than MnTeMoO<sub>6</sub> resultants, and their band gap energy decreases with increasing Ta-addition ratio at 2 ~ 8 mol%. The melting point of Ta:MnTeMoO<sub>6</sub> resultants decreases with increasing Ta-addition ratio that suggest the Ta:MnTeMoO<sub>6</sub> resultants would exhibit a weaker thermal damage threshold than MnTeMoO<sub>6</sub>. As the 1 mol% Ta-doping ratio, the resultant exhibits an obviously SHG efficiency of approximately 1.65× MnTeMoO<sub>6</sub>.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149035044","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}

引用次数: 0

Dymnikova black holes in unimodular gravity: Maxwell sources and vacuum contributions 单模引力中的Dymnikova黑洞：麦克斯韦源和真空贡献

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08299-9

G. Alencar, V. H. U. Borralho

引用次数: 0

Recent developments in particle flow calorimetry—a snapshot 颗粒流量热法的最新发展——简况

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08319-8

Mary Cruz Fouz, Roman Pöschl

引用次数: 0

Measurement uncertainty propagation in Makkink-based potential evapotranspiration: GUM analysis with AI-assisted Monte Carlo validation 基于makkin的潜在蒸散发的测量不确定度传播：人工智能辅助蒙特卡罗验证的GUM分析

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08328-7

Can Ekici, Başak Savun

引用次数: 0

Simulation of electron acceleration in a plasma-filled twisted elliptical waveguide: effect of twist angle 等离子体填充扭曲椭圆波导中电子加速的模拟：扭曲角的影响

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08323-y

Mahsa Mikaeili Baghi, Abbas Abdoli-Arani

{"title":"Simulation of electron acceleration in a plasma-filled twisted elliptical waveguide: effect of twist angle","authors":"Mahsa Mikaeili Baghi, Abbas Abdoli-Arani","doi":"10.1140/epjp/s13360-026-08323-y","DOIUrl":"10.1140/epjp/s13360-026-08323-y","url":null,"abstract":"<div><p>This study investigates the acceleration and dynamics of an electron injected into a plasma-filled, twisted elliptical waveguide with perfectly conducting walls, using COMSOL Multiphysics simulations. The electromagnetic fields inside the waveguide are first obtained from the electromagnetic solution, and the subsequent electron field interaction is analyzed using the relativistic momentum and energy equations. In the cold-plasma-filled twisted elliptical waveguide, the electron kinetic energy, acceleration gradient, deflection angle, trajectory, velocity components, and force components are presented and compared for different total twist angles. The study is then extended to a magnetized plasma-filled twisted elliptical waveguide under an externally applied static axial magnetic field. For this configuration, the electromagnetic field distributions, dispersion characteristics, scattering parameters, and electron dynamical behavior are analyzed. The results show that the twist angle significantly affects electron acceleration in both cold and magnetized plasma configurations. Within a certain range, increasing the twist angle enhances the electron kinetic energy and acceleration gradient, whereas further increase beyond this range reduces the energy. The corresponding changes in trajectory, deflection angle, velocity, and force components show that the twist rate plays an important role in controlling the interaction between the injected electron and the electromagnetic fields. Therefore, the proposed plasma-filled twisted elliptical waveguide provides a controllable structure to regulate and enhance the kinetic energy of an injected electron.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149035053","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}

引用次数: 0

Advancing semiconductor gamma detection: a Monte Carlo evaluation for nuclear medicine imaging 推进半导体伽马探测：核医学成像的蒙特卡罗评估

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08270-8

A. A. El-Rahman, H. G. Abdelwahed, M. A. Ghoneim

{"title":"Advancing semiconductor gamma detection: a Monte Carlo evaluation for nuclear medicine imaging","authors":"A. A. El-Rahman, H. G. Abdelwahed, M. A. Ghoneim","doi":"10.1140/epjp/s13360-026-08270-8","DOIUrl":"10.1140/epjp/s13360-026-08270-8","url":null,"abstract":"<div><p>In nuclear medicine, conventional scintillator materials suffer from poor energy resolution and reliance on bulky photomultiplier tube (PMT) designs. Semiconductor detectors such as cadmium telluride (CdTe) and cadmium zinc telluride (CZT) improve spatial resolution and sensitivity but remain costly with limited fields of view. Thallium bromide (TlBr), with higher density, strong stopping power, and room-temperature operation, offers a promising alternative. This study used Monte Carlo simulations to quantitatively evaluate TlBr performance in comparison with other compound semiconductor detectors. GATE v9.1 was used to simulate phantom models and compare TlBr imaging performance with CdTe and CZT for clinical use. Image quality was evaluated using sensitivity, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and full width at half maximum (FWHM). Results demonstrate that TlBr consistently has superior performance, achieving higher CNR, SNR, sensitivity, and spatial resolution than CdTe and CZT. At 7 mm, TlBr provided clearer phantom images, improved sphere edge definition, and higher SNR. Sensitivity increased with thickness for all materials but was highest for TlBr, reflecting its higher density and photon absorption efficiency. While improvements plateaued beyond 5 mm, TlBr maintained an advantage in resolution and noise reduction. TlBr is a suitable material for medical imaging, providing enhanced diagnostic accuracy and potential dose reduction compared to CdTe and CZT.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149035155","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}

引用次数: 0

Probing the accelerating Bertotti–Robinson black hole: thermodynamics, geodesics, and optical properties 探测加速Bertotti-Robinson黑洞：热力学、测地线和光学性质

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08341-w

Ahmad Al-Badawi, Faizuddin Ahmed, Edilberto O. Silva

{"title":"Probing the accelerating Bertotti–Robinson black hole: thermodynamics, geodesics, and optical properties","authors":"Ahmad Al-Badawi, Faizuddin Ahmed, Edilberto O. Silva","doi":"10.1140/epjp/s13360-026-08341-w","DOIUrl":"10.1140/epjp/s13360-026-08341-w","url":null,"abstract":"<div><p>We study the horizon thermodynamics, timelike and null geodesics, and optical properties of the accelerating Bertotti–Robinson (BR) spacetime, an exact Einstein–Maxwell electrovacuum configuration characterized by a uniform external magnetic field <i>B</i> and an acceleration parameter <span>(alpha)</span>. We first delimit the static region and distinguish the black-hole horizon from the acceleration horizon that is present when <span>(alpha >B)</span>. Since nonzero acceleration breaks reflection symmetry about <span>(theta =pi /2)</span>, massive circular motion is treated in the full <span>((r,theta ))</span> plane. We determine off-equatorial circular orbits, locate the innermost stable circular orbit from the coupled radial–polar stability problem, and obtain the two normal-mode frequencies of small perturbations. For null geodesics, the Hamilton–Jacobi equation separates after removal of the conformal factor. This yields a Carter-like constant, the constant-radius photon surface, the constant-latitude photon cone, the critical radial impact parameter, and the angular radius of the shadow for a finite static observer. We also discuss photon-cone trajectories, the effective radial force, the radial Lyapunov exponent, and a geometric-optics spectral proxy based on the critical capture scale. Analytic Schwarzschild and non-accelerating limits, together with the <span>(B=0)</span> C-metric limit, provide independent checks of the orbital analysis.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"141 9","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149035050","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}

引用次数: 0

Cascaded frequency conversion based on dynamical quantum geometric tensor 基于动态量子几何张量的级联变频

IF 2.9 3区物理与天体物理

The European Physical Journal Plus Pub Date : 2026-09-24 DOI: 10.1140/epjp/s13360-026-08275-3

Yongbo Xiao, Mingjie Lin, JiaYu Zhang, Yangeng Cui, Ziquan Zhou, Changshui Chen

引用次数: 0