Chaos Solitons & Fractals最新文献

{"title":"Time fractional evolution of two superconducting charge qubits","authors":"Abdessamie Chhieb ,&nbsp;Mansoura Oumennana ,&nbsp;Mostafa Mansour","doi":"10.1016/j.chaos.2025.117331","DOIUrl":"10.1016/j.chaos.2025.117331","url":null,"abstract":"<div><div>We investigate the quantum correlation dynamics between two superconducting charge qubits (TSC-Q), governed by the time-fractional Schrödinger equation (TFSE), a framework incorporating non-Markovian memory effects arising from environmental interactions. By analyzing separable and partially entangled initial states, we highlight the central role of the fractional order <span><math><mi>τ</mi></math></span>, Josephson energies (<span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>J</mi><mn>1</mn></mrow></msub></math></span>, <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>J</mi><mn>2</mn></mrow></msub></math></span>), and coupling strength (<span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>m</mi></mrow></msub></math></span>) in modulating concurrence, quantum steering asymmetry, and Bell nonlocality (via the CHSH inequality). Our results indicate that a decrease in the value of <span><math><mi>τ</mi></math></span> promotes a faster generation of quantum correlations for separable and partially entangled states, highlighting the dual role of <span><math><mi>τ</mi></math></span> as both a catalyst and a stabilizer of quantum resources. Furthermore, it is important to note that optimal behavior of quantum correlations is observed when the Josephson energies of the two qubits are close, i.e., when <span><math><mrow><msub><mrow><mi>E</mi></mrow><mrow><mi>J</mi><mn>2</mn></mrow></msub><mo>≈</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>J</mi><mn>1</mn></mrow></msub></mrow></math></span>. In addition, a stronger coupling strength, denoted by <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>m</mi></mrow></msub></math></span>, further enhances the generation of these correlations. The synergy among <span><math><mi>τ</mi></math></span>, <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>J</mi><mn>1</mn></mrow></msub></math></span>, <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>J</mi><mn>2</mn></mrow></msub></math></span>, and <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>m</mi></mrow></msub></math></span> defines a tunable parameter space for engineering memory-driven correlations to mitigate decoherence. These results position the TFSE as a promising tool for modeling non-Markovian dynamics in superconducting architectures, paving the way for robust quantum platforms with enhanced correlations, suitable for scalable quantum computing and secure communication systems.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117331"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complex-valued chaotic model with high chaos complexity and provable Lyapunov exponent","authors":"Yinxing Zhang ,&nbsp;Yukai Liu ,&nbsp;Tao Wang ,&nbsp;Jian Song ,&nbsp;Tao Shen","doi":"10.1016/j.chaos.2025.117282","DOIUrl":"10.1016/j.chaos.2025.117282","url":null,"abstract":"<div><div>Chaotic systems with high chaos complexity are the foundation of chaos-based applications. Owing to the existence of complex-valued variables and parameters, complex chaotic systems can exhibit intricate dynamics and high chaos complexity. Yet, research in this area remains largely concentrated on real chaotic systems. In light of this, we propose a two-dimensional complex chaotic model (2D-CCM) by combining modular operation and various entire functions. This framework enables the systematic generation of diverse two-dimensional complex chaotic maps suitable for chaos-based applications. To show its capability, two illustrative examples are presented and analyzed. Unlike most studies that rely solely on numerical validation, we provide a theoretical guarantee for the chaotic behavior exhibited by the proposed maps. Property analysis further reveals that the two complex maps exhibit rich dynamical behaviors with diverse chaotic features. Extensive experiments show that the generated maps outperform several representative systems in terms of chaos complexity metrics and have also been successfully implemented in hardware platform. In addition, pseudorandom number generators are constructed using the generated maps. The resulting sequences exhibit strong statistical randomness, as verified by both the NIST SP 800-22 and TestU01 test suites. Finally, when applied to the FH-OFDM-DCSK system under AWGN channels, they achieve lower bit error rates than existing maps. This highlights their robustness to noise and potential for secure applications.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117282"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145229015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting stock prices using permutation decision trees and strategic trailing","authors":"Vishrut Ramraj ,&nbsp;Nithin Nagaraj ,&nbsp;Harikrishnan N.B.","doi":"10.1016/j.chaos.2025.117352","DOIUrl":"10.1016/j.chaos.2025.117352","url":null,"abstract":"<div><div>In this paper, we explore the application of Permutation Decision Trees (PDT) and strategic trailing for predicting stock market movements and executing profitable trades in the Indian stock market. We focus on high-frequency data using 5-minute candlesticks for the top 50 stocks listed in the NIFTY 50 index and Forex pairs such as XAUUSD and EURUSD. We implement a trading strategy that aims to buy stocks at lower prices and sell them at higher prices, capitalizing on short-term market fluctuations. Due to regulatory constraints in India, short selling is not considered in our strategy. The model incorporates various technical indicators and employs hyperparameters such as the trailing stop-loss value and support thresholds to manage risk effectively. We trained and tested data on a 3 month dataset provided by Yahoo Finance. Our bot based on Permutation Decision Tree achieved a profit of 1.1802% over the testing period, where as a bot based on LSTM gave a return of 0.557% over the testing period and a bot based on RNN gave a return of 0.5896% over the testing period. All of the bots outperform the buy-and-hold strategy, which resulted in a loss of 2.29%.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117352"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145229014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel throttle-based self-stabilizing control scheme integrated into an anisotropic continuum model to mitigate cyber-attacks in connected vehicle scenarios","authors":"Cong Zhai ,&nbsp;Weitiao Wu ,&nbsp;Yingping Xiao ,&nbsp;Jiyong Zhang ,&nbsp;Min Zhai ,&nbsp;Yingzi Wu","doi":"10.1016/j.chaos.2025.117319","DOIUrl":"10.1016/j.chaos.2025.117319","url":null,"abstract":"<div><div>Since the unveiling of the technical architecture for vehicle-road-cloud unity, the technological advancements and industrial development of intelligent connected vehicles (ICVs) have been accelerated. However, the open inter-vehicle communication environment exposes ICVs to potential security threats from malicious hackers, which can compromise information sharing by tampering with transmission data. To address these challenges, we introduce the intensity coefficient of cyber-attacks into an original microscopic traffic flow model. In our model, a compensation algorithm leveraging historical data to fill the missing traffic information caused by malevolent cyber-attacks, and a self-stabilizing control scheme relying on electronic throttle (ET) angle dynamics are designed to enhance the robustness of traffic flow. The corresponding macroscopic version of the microscopic model is derived using a macroscopic-microscopic transformation approach. Through the implementation of the small perturbation approach, the stability criteria are identified by completing a linear stability analysis regarding the new models. The results show that the intensity coefficient of cyber-attacks, time gap and control gain term are intimately linked to the stability of traffic flow. We also determined the KdV-Burger's equation by performing the nonlinear analysis, and present its associated density wave solution. Finally, numerical simulations of the proposed model are conducted by adopting the first-order upwind approach and the principle of finite difference under both open and periodic boundary conditions. The simulation results corroborate the theoretical findings and also validate that the new model can mimic some typical scenarios in real-world scenarios, such as the accumulation and dissipation process of road traffic flow.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117319"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chiral supersolid and dissipative time crystal in Rydberg-dressed Bose–Einstein condensates with Raman-induced spin–orbit coupling","authors":"Xianghua Su,&nbsp;Xiping Fu,&nbsp;Yang He,&nbsp;Ying Shang,&nbsp;Kaiyuan Ji,&nbsp;Linghua Wen","doi":"10.1016/j.chaos.2025.117353","DOIUrl":"10.1016/j.chaos.2025.117353","url":null,"abstract":"<div><div>Spin–orbit coupling (SOC) is one of the crucial factors that affect the chiral symmetry of matter by causing the spatial symmetry breaking of the system. We find that Raman-induced SOC can induce a chiral supersolid phase with a helical antiskyrmion lattice in balanced Rydberg-dressed two-component Bose–Einstein condensates (BECs) in a harmonic trap by modulating the Raman coupling strength. This is in stark contrast to the mirror symmetric supersolid phase containing skyrmion–antiskyrmion lattice pair for the case of Rashba SOC. Two ground-state phase diagrams are presented as a function of the Rydberg interaction and the Raman-induced SOC. It is shown that the interplay among Raman-induced SOC, Rydberg interactions, and nonlinear contact interactions favors rich ground-state structures, including half-quantum vortex phase, stripe supersolid phase, toroidal stripe phase with a central Anderson–Toulouse coreless vortex, checkerboard supersolid phase, mirror symmetric supersolid phase, chiral supersolid phase and standing-wave supersolid phase. In addition, the effects of rotation and in-plane quadrupole magnetic field on the ground state of the system are analyzed. In these two cases, the chiral supersolid phase is broken and the ground state tends to form a miscible phase. Furthermore, we demonstrate that when the initial state is a chiral supersolid phase the rotating harmonic trapped system sustains dissipative continuous time crystal by studying the rotational dynamic behaviors of the system.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117353"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145229013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fabrication of a CVD-grown MoS2/DWCNT heterostructure as a saturable absorber for a mode-locked fiber laser","authors":"Bin Zhang ,&nbsp;Zhenyu Xu ,&nbsp;Zixuan Ning ,&nbsp;Xueyin Bai ,&nbsp;Jiancheng Zheng ,&nbsp;Qiang Zhang ,&nbsp;Shuyi Mi ,&nbsp;Weimin Sun ,&nbsp;Esko I. Kauppinen ,&nbsp;Li Li","doi":"10.1016/j.chaos.2025.117354","DOIUrl":"10.1016/j.chaos.2025.117354","url":null,"abstract":"<div><div>Nanomaterial heterostructures play an important role as saturable absorbers (SAs) for achieving mode-locking in ultrafast fiber lasers. However, current heterostructure fabrication methods for sandwich-structured SAs in all-fiber laser applications still face several technical challenges: mechanical exfoliation exhibits limitations in thickness controllability and preparation scale, liquid-phase exfoliation suffers from polymer residues and poor material homogeneity, while conventional chemical vapor deposition (CVD) methods, although free from these limitations during material preparation, typically require wet-transfer processes from growth substrates (e.g., silicon or sapphire) to fiber end-faces that often induce material wrinkling and contamination. To enable direct dry-transfer onto fiber end-faces, this study proposes a novel approach that combines floating-catalyst CVD (FC-CVD) and gas-phase CVD (GCVD) to synthesize substrate-free, mixed-dimensional MoS₂/DWCNT heterostructures. With a fixed MoS₂ thickness of 52 nm, two heterostructures were fabricated by changing DWCNT collection time: an 88-nm-thick (36-nm-thick DWCNT) SA with modulation depth of 1.0 %, saturation intensity of 43.9 MW/cm², and nonsaturable loss of 74.0 %; and a 70-nm-thick (18-nm-thick DWCNT) SA exhibiting modulation depth of 1.4 %, saturation intensity of 50.0 MW/cm², and nonsaturable loss of 69.4 %. Both heterostructures functioned effectively as SAs in erbium-doped fiber lasers (EDFLs), generating stable conventional soliton mode-locking with pulse widths of 1.26 ps (88-nm-thick SA) and 0.78 ps (70-nm-thick SA). The experimental results demonstrate that lower nonsaturable loss not only compresses the pulse width but also reduces the soliton generation time, consistent with theoretical simulation results from the complex nonlinear Ginzburg-Landau equation. We demonstrate that the two-step CVD method for synthesizing thickness-controlled heterostructure SAs provides a simple method for tuning mode-locked pulse widths.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117354"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stable high-charge vortex dissipative solitons in azimuthally modulated waveguide arrays with localized gain","authors":"Changming Huang ,&nbsp;Qidong Fu ,&nbsp;Li Ma","doi":"10.1016/j.chaos.2025.117314","DOIUrl":"10.1016/j.chaos.2025.117314","url":null,"abstract":"<div><div>We study the existence and dynamical properties of vortex solitons in Kerr media supported by azimuthally modulated waveguide lattices with localized gain and nonlinear loss. In this dissipative system, we find that the accessible topological charge of vortex solitons is strongly determined by the number of waveguide channels, with higher-order charges requiring progressively larger arrays. Power curves of vortex solitons with different charges exhibit clear separation in large arrays but become less distinguishable in smaller ones. Furthermore, these robust vortex solitons can be excited with nearly vanishing power thresholds, and higher-charge vortices display enhanced propagation stability compared with lower-charge states. These findings expand the family of dissipative vortex solitons supported by waveguide lattices and provide a route to the realization of stable high-symmetry vortex states.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117314"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive event-triggered robust distributed filter for nonlinear systems with non-stationary heavy-tailed noise","authors":"Yu Chen ,&nbsp;Yuanli Cai ,&nbsp;Jiaqi Liu ,&nbsp;Yifan Deng ,&nbsp;Haonan Jiang","doi":"10.1016/j.chaos.2025.117340","DOIUrl":"10.1016/j.chaos.2025.117340","url":null,"abstract":"<div><div>This paper investigates a novel adaptive event-triggered robust distributed filtering approach for nonlinear sensor networks under communication congestion and nonstationary heavy-tailed noise. To simultaneously ensure high estimation accuracy and low communication overhead, a hybrid model-based adaptive event-triggered mechanism is developed, enabling the dynamic adjustment of triggering thresholds and filter gains based on noise characteristics. A novel distributed filter based on this mechanism is then derived using a sequential fast covariance fusion scheme. Notably, to tackle the nonlinear integration challenge introduced by Student’s t-distribution weighting in the proposed algorithm, a new numerical integration method is proposed by combining cubature rule with Gauss–Laguerre quadrature, achieving high-accuracy approximation. Subsequently, the algorithm’s boundedness is analyzed, and sufficient conditions for mean-square exponential stability are provided. Finally, tracking simulations involving multiple unmanned aerial vehicles validate the effectiveness and superiority of the proposed method.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117340"},"PeriodicalIF":5.6,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Entropic analysis of a hierarchically organized Axelrod model","authors":"Marcos E. Gaudiano ,&nbsp;Jorge A. Revelli","doi":"10.1016/j.chaos.2025.117287","DOIUrl":"10.1016/j.chaos.2025.117287","url":null,"abstract":"<div><div>Hierarchically organized patterns are ubiquitously found in complex systems, however most Sociophysics models still assume random initial conditions. In this article, we study a simple and quasi-non-parametric version of Axelrod’s model of cultural dynamics, where individuals are initially arranged following structured spatial and ideological patterns. We explore how different levels of initial structural complexity influence the system’s evolution, identifying distinct regimes of controllability and cultural diversity, which can be interpreted through an entropy-based perspective. We show that maximum cultural diversification occurs within a specific range of initial structural organization, corresponding to a regime of high entropy and unpredictability. Moreover, we observe a quantization phenomenon, where only certain discrete types of final cultural configurations emerge.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117287"},"PeriodicalIF":5.6,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Independent and controllable space-time autofocused dual Airyprime Hermite complex-variable-function Gaussian fractional wave packets","authors":"Chao Tan ,&nbsp;Yong Liang ,&nbsp;Min Zou ,&nbsp;Mingwei Liu ,&nbsp;Lifu Zhang","doi":"10.1016/j.chaos.2025.117327","DOIUrl":"10.1016/j.chaos.2025.117327","url":null,"abstract":"<div><div>This work investigates the controllable spatiotemporal autofocusing characteristics of dual Airyprime Hermite complex-variable-function Gaussian (dAHCG) wave packets under the quadratic phase modulation (QPM) based on the fractional Schrödinger equation (FSE) optical system. By elaborately engineering the decay factor, distribution coefficient, Lévy index in both time and space domain, QPM coefficient and quadratic chirp, we achieve flexible control over the wave packet's morphology while enabling precise manipulation of its focal length and focal intensity. This approach facilitates simultaneous or asynchronous spatiotemporal self-focusing with significantly enhanced peak intensity at the space-time focal point. Our findings provide a new perspective on precisely tuning spatiotemporal self-focusing properties of wave packets and highlight the potential of these novel QPM-based wave packets in applications such as optical manipulation and laser processing.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"201 ","pages":"Article 117327"},"PeriodicalIF":5.6,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}