Chinese Journal of Physics最新文献

{"title":"CEEMDAN permutation entropy based statistical complexity measure: A new stochastic resonance metric for enhanced detection of feature-unknown weak signals","authors":"Shangbin Jiao ,&nbsp;Yin Zhu ,&nbsp;Qing Zhang ,&nbsp;Yi Wang ,&nbsp;Yuxing Li ,&nbsp;Chenjing Li ,&nbsp;Xiaohui Wang","doi":"10.1016/j.cjph.2025.08.036","DOIUrl":"10.1016/j.cjph.2025.08.036","url":null,"abstract":"<div><div>When studying the adaptive nonlinear stochastic resonance (SR) with noisy periodic signal excitation, the system output resonance effect is typically measured using signal-to-noise ratio (SNR) or SNR gain. However, in practical engineering measurements, the SNR of the noisy input signal is often unknown. To overcome this limitation, this paper proposes a novel metric, “statistical complexity measure based on CEEMDAN permutation entropy (CEEMDAN-PE based SCM)”, to quantify the resonance output effect of the SR system, addressing the challenge of detecting weak signals with unknown features in engineering applications. First, the CEEMDAN is used to preprocess the feature-unknown input signal, and the optimal intrinsic mode function (IMF) is selected. This effectively addresses the modal aliasing problem in EMD that leads to inaccurate experimental results. It also helps filter complex noise components from the signal, aiding effective feature extraction in the subsequent SR processing. Secondly, the improved SCM is selected as the fitness function for the Harris Hawks Optimization (HHO) algorithm, optimizing the best matching parameters of the piecewise linearized bistable SR (PLBSR) system, thus achieving enhanced detection of weak signals with noisy inputs and unknown feature parameters. Simulation experiments show that the proposed CEEMDAN-PE based SCM method can effectively measure the resonance effect of the PLBSR system output and achieve enhanced detection of weak periodic signals. It is also capable of characterizing the system's dynamic complexity and has the potential to detect subtle behaviors induced by noise. Practical experiments demonstrate that the proposed SR measurement method performs well in bearing fault feature extraction.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"98 ","pages":"Pages 59-72"},"PeriodicalIF":4.6,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Statistics of non-monochromatic photons interacting with free electrons","authors":"K.A. Makarova ,&nbsp;D.N. Makarov","doi":"10.1016/j.cjph.2025.08.032","DOIUrl":"10.1016/j.cjph.2025.08.032","url":null,"abstract":"<div><div>It is well known that the interaction of photons with free electrons leads to their quantum entanglement and new statistics. Often, the study of the statistical properties of photons during their interaction with matter is considered for monochromatic photons. In reality, there are no completely monochromatic photons, and this must be taken into account. In this paper, it is shown that the statistical properties of non-monochromatic photons and their quantum entanglement can differ significantly from the case of monochromatic photons. It is shown that the photon statistics can be changed quite easily by varying the parameter responsible for the width of the spectral line of photons. The results obtained can be used in quantum technologies where photon states are needed that are not realized by other methods.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 systematic computational study on Na-based complex hydrides NaMXH6 (M = Sr, Ba; X = Co, Rh, Ir): A promising class of hydrogen storage materials","authors":"Khidhir Alhameedi ,&nbsp;Asif Hosen ,&nbsp;Heider A. Abdulhussein ,&nbsp;Nadia Ezzat Al-kirbasee ,&nbsp;Ali Akremi ,&nbsp;Imed Boukhris","doi":"10.1016/j.cjph.2025.08.033","DOIUrl":"10.1016/j.cjph.2025.08.033","url":null,"abstract":"<div><div>In this work, density functional theory (DFT) calculations are employed to explore the structural, mechanical, dynamical, optical, thermal, and hydrogen storage properties of NaMXH₆ complex hydrides (M = Sr and Ba; and X = Co, Rh, and Ir). Our findings revealed that all the investigated compounds crystallize in a cubic structure with space group F<span><math><mrow><mover><mn>4</mn><mo>¯</mo></mover><mn>3</mn></mrow></math></span><em>m</em> (No. 216). Phonon dispersion analysis confirms the dynamic stability of the materials, while <em>ab initio</em> molecular-dynamics (AIMD) simulations demonstrate their thermal stability, with no structural deformation. All compounds exhibit indirect band gap semiconductor behavior based on their electronic properties. The band gap decreases when M and/or X cations of NaMXH₆ are substituted. Optical property analysis reveals dual absorption regions in visible and ultraviolet spectra, with absorption coefficients reaching up to 1.4 × 10⁶ cm⁻¹, indicating strong potential for optoelectronic applications and light energy harvesting. To assess mechanical characteristics, the elastic constants were calculated and found to satisfy the mechanical stability criteria, confirming that these hydrides are generally brittle, hard, and stiff. Among them, NaSrCoH₆ shows the highest stiffness and resistance to deformation, while Ba-based hydrides exhibit enhanced ductility. The Quasi-Harmonic Debye model was employed to analyze thermodynamic behavior across a range of temperatures, with results aligning well with fundamental thermodynamic principles. The hydrogen storage capacities wt% of NaSrCoH₆, NaSrRhH₆, NaSrIrH₆, NaBaCoH₆, NaBaRhH₆, and NaBaIrH₆ are 3.44, 2.76, 1.96, 2.68, 2.25, and 1.69, respectively. Overall, these results demonstrate that NaMXH₆ hydrides are multifunctional materials with promising hydrogen storage capacity, mechanical resilience, and semiconducting behavior, making them suitable for clean energy technologies.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1240-1254"},"PeriodicalIF":4.6,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Performance modulation of ZnO/WSSe heterojunction photodetectors via longitudinal stress bending","authors":"Xiaoyu Zhao ,&nbsp;Yang Shen ,&nbsp;Zhen Cui ,&nbsp;Ke Qin ,&nbsp;Deming Ma ,&nbsp;Fengjiao Cheng ,&nbsp;Pei Yuan ,&nbsp;Xiangfeng Qi ,&nbsp;Enling Li","doi":"10.1016/j.cjph.2025.08.031","DOIUrl":"10.1016/j.cjph.2025.08.031","url":null,"abstract":"<div><div>In the practical application of photodetectors, they are often subjected to external bending forces. To explore the influence of stress bending, this study constructed a novel heterojunction ZnO/WSSe with two configurations: ZnO-Se and ZnO-S. The stability of these heterojunctions was confirmed through calculations of formation energy, phonon spectrum analysis, and AIMD simulations. Electronic property studies revealed different band configurations. ZnO-Se exhibited a type-I heterojunction with a bandgap of 2.18 eV, while ZnO-S formed a type-II heterojunction with a bandgap of 1.88 eV. Despite the same composition, different interface states led to different electrostatic potentials. Optical property analysis indicated that both heterojunctions had enhanced light absorption compared to the intrinsic materials. The heterojunction photodetectors demonstrated significant photocurrent response and exhibited a negative differential resistance effect in their I-V characteristics, indicating different turn-on voltages. Longitudinal stress bending experiments further showed effective modulation of photocurrent response and I-V characteristics, highlighting mechanical stress engineering as a means to enhance performance. In summary, these findings highlight the potential of ZnO-Se and ZnO-S heterojunctions in optoelectronic applications.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"98 ","pages":"Pages 137-146"},"PeriodicalIF":4.6,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145109197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Magnetic moments of hidden-charm pentaquarks in the diquark–diquark–antiquark scheme","authors":"Halil Mutuk","doi":"10.1016/j.cjph.2025.07.030","DOIUrl":"10.1016/j.cjph.2025.07.030","url":null,"abstract":"<div><div>The magnetic moment of a hadron is an important spectroscopic parameter that encodes valuable information about its internal structure. In this work, we systematically investigate the magnetic moments of hidden-charm pentaquark states, including the experimentally observed <span><math><mrow><msub><mrow><mi>P</mi></mrow><mrow><mi>c</mi></mrow></msub><mrow><mo>(</mo><mn>4457</mn><mo>)</mo></mrow></mrow></math></span> and related configurations with and without strangeness. The analysis is performed within the diquark–diquark–antiquark framework for spin-parity quantum numbers <span><math><mrow><msup><mrow><mi>J</mi></mrow><mrow><mi>P</mi></mrow></msup><mo>=</mo><msup><mrow><mfrac><mrow><mn>1</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow><mrow><mo>−</mo></mrow></msup></mrow></math></span>, <span><math><msup><mrow><mfrac><mrow><mn>3</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow><mrow><mo>−</mo></mrow></msup></math></span>, and <span><math><msup><mrow><mfrac><mrow><mn>5</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow><mrow><mo>−</mo></mrow></msup></math></span>. Magnetic moment values are computed for different spin and flavor configurations, and the results are compared with existing predictions in the literature. These predictions may offer insight into the inner structure and quantum numbers of these exotic states, and potentially help distinguish between different theoretical models.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1406-1414"},"PeriodicalIF":4.6,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145010323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Exact quantum Rindler frames from an algebraic approach","authors":"Otto C.W. Kong","doi":"10.1016/j.cjph.2025.08.026","DOIUrl":"10.1016/j.cjph.2025.08.026","url":null,"abstract":"<div><div>We have developed the Heisenberg picture approach to quantum mechanics in spacetime with an arbitrary metric and obtained quantum geodesic equations in a previous publication. The picture naturally fits in with the recently popular topic of quantum reference frame transformations, suggesting treating the different position observables as coordinate observables of spacetime. We see that as an approach to quantum physics that is very much along the original idea of Heisenberg and Dirac, completed now with explicit mathematical expressions for Dirac’s notion of q-number values of observables. Quantum physics can be analyzed as such, independent of any Schrödinger picture. Beyond the Cartesian coordinate pictures, correspondence between the Heisenberg and the Schrödinger picture is generally nontrivial, depending on the metric expression and the frame of reference. We focus on the algebraic approach for the Heisenberg-Dirac picture to formulate transformations to exact quantum Rindler frames with quantum proper accelerations. The latter has been considered by various authors in semiclassical treatments. Analyses of some interesting results are presented. The characteristic feature of quantum reference frame transformations in giving rise to entanglement features when the particle to serve as the new frame is in a nontrivial superposition of eigenstates for the observable defining the transformation, the proper acceleration in this case, is illustrated. The notion of other ‘quantum Rindler observers’ is also analyzed. The metric in the quantum Rindler frame is illustrated to become a nonlocal observable with profound implications of which are also discussed. The question about unitarity of the transformations is carefully addressed. Discussions about a consistent perspective on the general subject matter with a quantum picture of spacetime and its Quantum Relativity Principle are also presented.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1293-1305"},"PeriodicalIF":4.6,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144931914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Comments on the paper “The structural, electronic and magnetic properties of Fe3ZnC anti-perovskite”","authors":"Hoseung Jang,&nbsp;Unjong Yu","doi":"10.1016/j.cjph.2025.08.029","DOIUrl":"10.1016/j.cjph.2025.08.029","url":null,"abstract":"<div><div>We revisit the magnetic phase transition in the spin-5/2 <span><math><mrow><msub><mi>J</mi><mn>1</mn></msub><mspace></mspace><mo>−</mo><mspace></mspace><msub><mi>J</mi><mn>2</mn></msub></mrow></math></span> Blume–Capel model, proposed to describe the magnetic properties of Fe<span><math><msub><mrow></mrow><mn>3</mn></msub></math></span>ZnC in the recently published paper ”The structural, electronic and magnetic properties of Fe<span><math><msub><mrow></mrow><mn>3</mn></msub></math></span>ZnC anti-perovskite” by Hajjami et al., using the Monte Carlo method combined with finite-size scaling analysis. Our results verify that the magnetic phase transition is continuous and belongs to the three-dimensional Ising universality class. The critical temperature is determined to be <span><math><mrow><msub><mi>T</mi><mi>c</mi></msub><mo>=</mo><mn>23.63</mn><mrow><mo>(</mo><mn>1</mn><mo>)</mo></mrow></mrow></math></span> K, which is close to a mean-field theory estimate but significantly lower than the value reported by Hajjami et al., raising questions about the validity of their computational analysis. Moreover, the discrepancy in critical temperature between our results and experimental observations suggests that the proposed spin model or parameter set may require reevaluation to properly describe the magnetic properties of Fe<span><math><msub><mrow></mrow><mn>3</mn></msub></math></span>ZnC.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1213-1217"},"PeriodicalIF":4.6,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Dynamics of singularity-free anisotropic solutions for charged compact stars in general relativity","authors":"M. Sharif ,&nbsp;Tayyab Naseer ,&nbsp;Hira Shadab","doi":"10.1016/j.cjph.2025.08.027","DOIUrl":"10.1016/j.cjph.2025.08.027","url":null,"abstract":"<div><div>This study introduces two unique, singularity-free solutions for anisotropic spherical systems coupled with an electromagnetic field. We firstly derive the Einstein-Maxwell equations for a static spherically symmetric spacetime. The corresponding anisotropy is then introduced which we use to determine our solutions. To ensure physical validity of the proposed models, we outline several conditions whose fulfilment is essential. The field equations are solved under two constraints, such as varying forms of the radial metric function and the anisotropic pressure. These assumptions yield two second-order differential equations in terms of the temporal component whose solutions involve integration constants. We fix these constants by matching the interior metric and the Reissner-Nordström exterior spacetime at the boundary. We also impose vanishing radial pressure at the surface to determine these constants. Using observed masses and radii of six star pulsars, we analyze the proposed solutions graphically for different charge values. Both models satisfy all physical conditions, demonstrating that the anisotropic matter distributions accurately describe compact stars under the Einstein’s gravity theory.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1386-1405"},"PeriodicalIF":4.6,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Tunable multiple magnomechanically induced transparency windows and controllable fast-slow light in a cavity-magnon-phonon hybrid system","authors":"Fazal Badshah ,&nbsp;Jin Xie ,&nbsp;Muhammad Idrees Afridi ,&nbsp;Sun Jiaxin ,&nbsp;Muhammad Idrees ,&nbsp;Wu Wenhuan","doi":"10.1016/j.cjph.2025.08.028","DOIUrl":"10.1016/j.cjph.2025.08.028","url":null,"abstract":"<div><div>We study magnomechanically induced transparency (MMIT) with two yttrium iron garnet spheres in a microwave cavity with different interaction parameters. According to numerical simulations, the steady-state magnon number is sensitive to both bias and drive magnetic fields and rises with a stronger coupling between cavity photons and magnons. The significance of the bias field in energy transfer is demonstrated by prominent peaks in the magnon population close to resonant fields. The transmission spectrum shows that the coupling and magnon-phonon interactions determine the tunable transparency windows, which can have up to four peaks. By identifying normal and anomalous regions through dispersion analysis, slow and fast light propagation are achieved, which is influenced by the coupling strength. Variations in phase and group delay, which are affected by the drive field, provide additional evidence that transparency windows are tunable. We assert that this work shows how MMIT can be used for precise control over light-matter interactions without the need for extra nonlinearity, with potential applications in optical communications and quantum information processing.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1374-1385"},"PeriodicalIF":4.6,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Exact solutions for the Davey-Stewartson I equation obtained from auto-Bäcklund transformation related to nonlocal residual symmetry","authors":"Xueping Cheng,&nbsp;Mengyuan Zhao","doi":"10.1016/j.cjph.2025.08.017","DOIUrl":"10.1016/j.cjph.2025.08.017","url":null,"abstract":"<div><div>In this paper, the nonlocal residual symmetry associated with the Painlevé truncation expansion of the Davey-Stewartson I equation is derived. After localizing the nonlocal symmetry into a local one and solving the corresponding initial value problem, the auto-Bäcklund transformation related to this nonlocal symmetry is presented. Making full use of the auto-Bäcklund transformation, different types of exact solutions for the Davey-Stewartson I equation can be constructed. Here, by selecting the seed expansion function as an exponential function, a rational function, etc., the soliton solution, solitoff solution, rogue wave solution and soliton-periodic wave interaction solution to the Davey-Stewartson I equation are designed. To specifically analyze their dynamic behaviors, the three-dimensional evolution profiles and density plots for these exact solutions with particular choices of the involved free parameters are effectively illustrated.</div></div>","PeriodicalId":10340,"journal":{"name":"Chinese Journal of Physics","volume":"97 ","pages":"Pages 1306-1315"},"PeriodicalIF":4.6,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144931915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}