Physica Scripta最新文献_第3页

Directional switching behavior of swarming systems with social and nonlinear interactions 具有社会和非线性相互作用的蜂群系统的定向切换行为

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-18 DOI: 10.1088/1402-4896/ad7916

Wang Li, Shijie Liu, Donghua Zhao and Yongzheng Sun

{"title":"Directional switching behavior of swarming systems with social and nonlinear interactions","authors":"Wang Li, Shijie Liu, Donghua Zhao and Yongzheng Sun","doi":"10.1088/1402-4896/ad7916","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7916","url":null,"abstract":"Coordinated directional switching can occur among members of many mobile biological communities. Some studies show that self-propelled particle models can describe the directional switching behavior well. The key to understanding group movement is to determine the influential factors relevant to directional switching behavior. This paper focuses on the impact of social and nonlinear interactions on the directional switching behavior observed in swarming systems. In which, the nonlinear interaction is represented as a function of a trade-off between the velocity and velocity direction of its neighbors. Based on the framework of dimension reduction theory, the high-dimensional complex model is simplified into a one-dimensional simple model, and the stationary probability density and mean switching time are obtained by theoretical analysis of the one-dimensional model. It can be seen that social and nonlinear interactions play an important role in regulating the directional switching behaviors of swarming systems. Specifically, the increase of group density and nonlinear parameter can inhibit the directional switches. For Erdös-Rényi networks, the large mean degree can suppress the directional switching behavior. For scale-free networks, increasing the degree heterogeneity can reduce the mean switching time. The results reveal the underlying mechanisms by which social and nonlinear interactions influence the directional switching behaviors of swarming systems, and provide a theoretical foundation for the design of bio-inspired devices with specific functions.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":"5 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257479","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

Multi-polarized four-mode wideband vortex electromagnetic beams generation through reflective metasurface in Ka-band 通过 Ka 波段反射元面产生多极化四模宽带涡旋电磁波束

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-18 DOI: 10.1088/1402-4896/ad7649

Lu Tian, Rui Zhang, Yong Wang, Bingchuan Xie, Haixuan Li and Yueyan Ren

{"title":"Multi-polarized four-mode wideband vortex electromagnetic beams generation through reflective metasurface in Ka-band","authors":"Lu Tian, Rui Zhang, Yong Wang, Bingchuan Xie, Haixuan Li and Yueyan Ren","doi":"10.1088/1402-4896/ad7649","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7649","url":null,"abstract":"Orbital angular momentum (OAM) is a new dimension for improving channel capacity and has been widely studied by scientists. In recent years, there has been an increasing amount of research on antennas and electromagnetic (EM) beams containing OAM, demonstrating its excellent ability in communication. This article proposes a Ka-band multi-mode orbital angular momentum reflectarray antenna (RA) capable of generating four vortex EM beams with four modes (l = −1, 0, +1, +2). The proposed unit cell can cover a 360-degree reflection phase range with a magnitude above 0.88, achieved through a combination of variable-sized and delay-line units. Furthermore, the unit cell’s mirror configuration allows for cross-polarization rejection. Based on these unit cells, a square reflectarray antenna (25 × 25 elements) is designed, fabricated, and measured. The measured results demonstrate that the 1 dB bandwidths for four modes are 25.81% (27–35 GHz, l = −1), 31.25% (27–37 GHz, l = 0), 28.57% (27–36 GHz, l = +1), and 20.69% (26–32 GHz, l = +2), respectively. Notably, the 3 dB gain bandwidths of all modes exceed 40%, with the maximum 3 dB bandwidth reaching 47.62% at mode l = +1. Furthermore, all vortex EM beams of this proposed RA maintain mode purities exceeding 70% within 3 dB bandwidths.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":"39 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257429","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

Polarization-dependent near-field coupling and far-field harmonic modulation in a graphene-based plasmonic nanostructure 石墨烯基等离子纳米结构中的偏振相关近场耦合和远场谐波调制

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad78ca

Ye Ming Qing, Zhaoyan Yang, Yunxia Wang, Yongze Ren and Jun Wu

{"title":"Polarization-dependent near-field coupling and far-field harmonic modulation in a graphene-based plasmonic nanostructure","authors":"Ye Ming Qing, Zhaoyan Yang, Yunxia Wang, Yongze Ren and Jun Wu","doi":"10.1088/1402-4896/ad78ca","DOIUrl":"https://doi.org/10.1088/1402-4896/ad78ca","url":null,"abstract":"The interplay between light and matter has fostered innovative research in surface plasmons, specifically in graphene, due to its tunable Fermi energy and reduced losses in the infrared and terahertz spectra. This study explores the anisotropic coupling of nonlocalized surface plasmons in graphene with localized magnetic polaritons (MP) in a silicon carbide (SiC) array. By adjusting graphene’s Fermi energy and polarization angle, we successfully achieved hybrid coupling, giving rise to three clearly distinguishable hybridized states. Using the coupled oscillator model as a framework, we conducted an analysis of the intricate multimode coupling and accurately ascertained the weighting efficiencies of the individual modes comprising the hybrids. By integrating the design principles of space-time coding metasurfaces, we successfully broadened the scope of the application, extending its reach from the near-field to the far-field. These novel discoveries pave new paths for advancements in thermal emitters, photonic systems, energy conversion technologies, and the creation of cutting-edge plasmonic devices.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":"29 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257492","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

Dual-channel photonic crystal fiber dual-parameter sensor exploiting surface plasmon resonance 利用表面等离子体共振的双通道光子晶体光纤双参数传感器

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad7893

Tengfei Xu, Shengli Pu, Siyang Huang and Yu Ji

引用次数: 0

A Mathematical Aspect of Bloch’s Theorem 布洛赫定理的数学方面

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad7767

Yan Li, Bin Yang and Aihui Zhou

引用次数: 0

A novel numerical method to solve fractional ordinary differential equations with proportional Caputo derivatives 解决带比例卡普托导数的分数常微分方程的新型数值方法

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad7897

Yogita M Mahatekar and Pushpendra Kumar

引用次数: 0

Investigation into geometric configurations and electronic properties of CeO2-supported gold clusters 研究 CeO2 支持的金簇的几何构型和电子特性

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad77f9

Pengli Shu, Xin Tian, Qiang Guo, Xiaosen Ren, Bohui Zhao, Huanfei Wen, Jun Tang, Yanjun Li, Sugawara Yasuhiro, Zongmin Ma and Jun Liu

{"title":"Investigation into geometric configurations and electronic properties of CeO2-supported gold clusters","authors":"Pengli Shu, Xin Tian, Qiang Guo, Xiaosen Ren, Bohui Zhao, Huanfei Wen, Jun Tang, Yanjun Li, Sugawara Yasuhiro, Zongmin Ma and Jun Liu","doi":"10.1088/1402-4896/ad77f9","DOIUrl":"https://doi.org/10.1088/1402-4896/ad77f9","url":null,"abstract":"A detailed understanding of the geometric structure and electronic properties of gold nanoparticles on the ceria surface is crucial for comprehending their unique catalytic activity. Using the first-principles method based on density functional theory, the adsorption of Aux (x = 1–4) clusters on the CeO2(111) surface was studied. It was discovered that the standing configurations of Au2 and Au3, as well as the tetrahedral structure of Au4, are the most stable adsorption structures. The stability of these configurations is jointly determined by the number and strength of Au-Au bonds, the Au-O bonding energy, and the interaction dynamics between the clusters and the substrate. The analysis of Bader charge, difference charge density and density of states suggested that lattice relaxation and electronic localization occur in the reduced Ce3+. The reduced amount and location of Ce3+ are significantly influenced by the position and charge transfer amount of Aux cluster. The adsorption of CO on Au4/CeO2(111) indicated that stronger Au-C bonding energy due to the hybridization of Au-5d and C-2p, thereby enhancing the catalytic activity for CO oxidation reactions.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":"75 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257486","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

A novel image encryption method based on the cycle replacement 基于循环替换的新型图像加密方法

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad7898

Pu Wang, Xiaojun Liu, Jing Xu and Chenhao Lu

{"title":"A novel image encryption method based on the cycle replacement","authors":"Pu Wang, Xiaojun Liu, Jing Xu and Chenhao Lu","doi":"10.1088/1402-4896/ad7898","DOIUrl":"https://doi.org/10.1088/1402-4896/ad7898","url":null,"abstract":"For the bit-level image encryption algorithms, pixel values and positions can be changed simultaneously. The operation can enhance the security of image encryption but will require the complicated calculations. Therefore, high security and suitable computation for a new algorithm are needed to be considered. In this paper, a novel image encryption algorithm, which combines the bit-level encryption and the pixel-level encryption methods, is proposed based on the cycle replacement. Firstly, a new 2-dimensional (2D) map with a hyperbolic cosine function (2D-Cosh map) is introduced, which has rich and complex dynamics. Based on the chaotic characteristic of the map, an image encryption algorithm is introduced via the substitution of bit of pixels which can scramble the pixels, and change the image pixel positions effectively. Numerical simulation and security analysis are used to demonstrate the effectiveness and feasibility of the algorithm. From which we can see that the correlation coefficients are almost 0, average entropy = 7.9973, average NPCR = 99.6104%, and average UACI = 33.4664%. It is clear that the algorithm is resistant to differential attacks, interference attacks, and can reduce the correlation of adjacent pixels of the encrypted image greatly. Meanwhile, the algorithm has no limit for the size of a color image in the process of the encryption.","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":"8 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257489","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

A front-fixing numerical method for a fluvio-deltaic sedimentation process with thespace fractional derivative and variable sediment flux 具有空间分数导数和可变沉积通量的流体-三角洲沉积过程的前固定数值方法

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad78c6

Jaya Joshi, Rajeev, J F Gómez-Aguilar and J E Lavín-Delgado

引用次数: 0

Contraction of ZX diagrams with triangles via stabiliser decompositions 通过稳定器分解收缩带三角形的 ZX 图

IF 2.9 3区物理与天体物理

Physica Scripta Pub Date : 2024-09-17 DOI: 10.1088/1402-4896/ad6fd8

Mark Koch, Richie Yeung and Quanlong Wang

{"title":"Contraction of ZX diagrams with triangles via stabiliser decompositions","authors":"Mark Koch, Richie Yeung and Quanlong Wang","doi":"10.1088/1402-4896/ad6fd8","DOIUrl":"https://doi.org/10.1088/1402-4896/ad6fd8","url":null,"abstract":"Recent advances in classical simulation of Clifford+T circuits make use of the ZX calculus to iteratively decompose and simplify magic states into stabiliser terms We improve on this method by studying stabiliser decompositions of ZX diagrams involving the triangle operation. We show that this technique greatly speeds up the simulation of quantum circuits involving multi-controlled gates which can be naturally represented using triangles. We implement our approach in the QuiZX library (2022 A. Kissinger amd J. van de Wetering Quantum Science and Technology7, 044001), (2022 A. Kissinger et al F. Le Gall and T. Morimae, ed. 17th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2022), Leibniz International Proceedings in Informatics (LIPIcs) 232, Schloss Dagstuhl—Leibniz-Zentrum für Informatik, Dagstuhl, Germany, pp 5:1–5:13) and demonstrate a significant simulation speed-up (up to multiple orders of magnitude) for random circuits and a variation of previously used benchmarking circuits. Furthermore, we use our software to contract diagrams representing the gradient variance of parametrised quantum circuits, which yields a tool for the automatic numerical detection of the barren plateau phenomenon in ansätze used for quantum machine learning. Compared to traditional statistical approaches, our method yields exact values for gradient variances and only requires contracting a single diagram. The performance of this tool is competitive with tensor network approaches, as demonstrated with benchmarks against the quimb library (2018 J. Gray Journal of Open Source Software3, 819).","PeriodicalId":20067,"journal":{"name":"Physica Scripta","volume":"43 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257484","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