The European Physical Journal B最新文献

{"title":"Effects of external stimuli on the dynamics of deterministic and stochastic Hindmarsh–Rose neuron models","authors":"Cesar Manchein,&nbsp;Paulo C. Rech","doi":"10.1140/epjb/s10051-024-00751-y","DOIUrl":"10.1140/epjb/s10051-024-00751-y","url":null,"abstract":"<div><p>We investigate the nonlinear dynamics of the deterministic and stochastic Hindmarsh–Rose (HR) neuron models under the influence of an external sinusoidal electric current and magnetic flow effects. In the deterministic regime, in the absence of a magnetic field, we observe multistability between periodic and chaotic attractors. This is accompanied by the emergence of self-similar windows of chaotic dynamics that converge within a broad domain of periodic dynamics in parameter space. Introducing a magnetic flux partially suppresses chaotic dynamics while maintaining multistability. Under stochastic conditions due to the introduction of Gaussian noise with arbitrarily small intensity, <i>D</i>, noise triggers transitions between coexisting states, exhibiting a preference for specific attractors from the deterministic case without returning to any other coexisting metastable states. By increasing <i>D</i> and appropriately adjusting the remaining control parameters of the HR neuron model, it becomes feasible to achieve regimes of noise-induced chaos or noise-induced stabilization, effectively suppressing chaotic dynamics. Furthermore, within this framework, we explore the existence of transient chaotic dynamics.</p></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 8","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141943195","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":"Solving Schrödinger equation within arbitrary spherical quantum dots with neural network","authors":"A. Naifar,&nbsp;K. Hasanirokh","doi":"10.1140/epjb/s10051-024-00759-4","DOIUrl":"10.1140/epjb/s10051-024-00759-4","url":null,"abstract":"<div><p>In this study, we delve into the realm of solving the Schrödinger equation within spherical quantum dots (QDs) characterized by arbitrary potentials, leveraging the capabilities of machine learning methodologies. Our approach involves training neural networks (NNs) through a curated collection of potentials and wave functions (WFs), which were initially computed using the classical finite element method. To gauge the reliability of the estimates produced by these NNs, we introduce accuracy indicators for rigorous assessment. The training procedure relies on the gradient descent method to optimize the networks’ performance. Furthermore, our investigation encompasses scenarios with analytical potentials, broadening the scope of our analysis beyond empirical cases. By integrating analytical potentials into our study, we aim to achieve a comprehensive understanding of the neural network’s effectiveness in handling various potential profiles. This expansion opens avenues for more versatile and insightful quantum mechanical explorations within the realm of nanoscale systems. Among the findings, the QD core exhibited the highest level of accuracy in WF estimation, achieved through the utilization of a spherical potential. Conversely, the estimation performance was least reliable in scenarios involving HLP, with a notable deviation of 16.68%. Transitioning to the core/shell structure, employing the double HLP configuration resulted in the most precise estimation of WFs. This contrasts significantly with the estimation performance for the V-Shaped Potential, where accuracy was comparatively lower with deviation of 4%.</p><h3>Graphical Abstract</h3><p>In this work, we solved the Schrödinger equation within spherical quantum dots characterized by arbitrary potentials, leveraging the capabilities of machine learning methodologies. Our approach includes training neural networks through a curated collection of potentials and wave functions, which were initially computed using the classical finite element method. By integrating analytical potentials into our study, we aim to achieve a comprehensive understanding of the neural network’s effectiveness in handling various potential profiles. The estimation performance was least reliable in scenarios involving HLP, with a notable deviation of 16.68%. Transitioning to the core/shell structure, employing the double HLP configuration resulted in the most precise estimation of WFs. This contrasts significantly with the estimation performance for the V-Shaped Potential (VP), where accuracy was comparatively lower with deviation of 4%</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 8","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141881382","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":"Structural and topological properties of the interface between amorphous silica and sodium tetrasilicate glass studied by molecular dynamics simulation","authors":"D. Stock,&nbsp;R. Linke,&nbsp;A. Heft,&nbsp;B. Grünler","doi":"10.1140/epjb/s10051-024-00754-9","DOIUrl":"10.1140/epjb/s10051-024-00754-9","url":null,"abstract":"<div><p>Classical molecular dynamics simulations are used to study structural properties of a planar interface between amorphous silica and sodium tetrasilicate glass in a dry environment. The interface region is characterised by the change of the network connectivity. The effect of the interfacial microstructure on the diffusion of sodium is analysed within the framework of topological constraint theory. It is shown that the interface represents an elastic phase boundary where a transition to a stressed-rigid phase occurs. The onset of rigidity in the interface region makes the out-diffusion of sodium from the sodium silicate glass more difficult. The topological controlled diffusion kinetics provides an explanation for the barrier property of amorphous silica despite its open network structure.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 8","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141881383","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":"A deep learning architecture using hybrid and stacks to forecast weekly dengue cases in Laos","authors":"Sathi Patra,&nbsp;Soovoojeet Jana,&nbsp;Sayani Adak,&nbsp;T. K. Kar","doi":"10.1140/epjb/s10051-024-00752-x","DOIUrl":"10.1140/epjb/s10051-024-00752-x","url":null,"abstract":"<p>Dengue is an arthropod-borne viral disease prevalent in tropical and subtropical regions. Its adverse impact on human health and the global economy cannot be exaggerated. To improve the efficacy of vector control measures, there is a critical need for mechanisms that can forecast dengue cases with greater accuracy and urgency than before. So, we employ some deep learning techniques using the previous ten years of weekly dengue cases in Laos. A hybrid model combining CNN and stacked LSTM (BiLSTM) is applied along with CNN, LSTM, BiLSTM, and ConvLSTM in this work. Comparing all the outputs we have derived, hybrid CNN and 1 stacked BiLSTM outperform other deep learning models with the one-step-ahead prediction. Further, we have concluded that hybrid CNN and 1 stacked BiLSTM can considerably boost dengue prediction and can be applied in other dengue-prone regions.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 8","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868968","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":"Theoretical investigation of the sensing capabilities of intrinsic and Fe-modified net-Y on SF(_6) decomposition products","authors":"Shun-Yu Wang,&nbsp;Zhi-Gang Shao,&nbsp;Cang-Long Wang,&nbsp;Lei Yang","doi":"10.1140/epjb/s10051-024-00755-8","DOIUrl":"10.1140/epjb/s10051-024-00755-8","url":null,"abstract":"<p>Detection of SF<span>(_6)</span> decomposition gases is crucial in power equipment maintenance. This paper investigates the adsorption behavior of SO<span>(_2)</span> and H<span>(_2)</span>S on the intrinsic and Fe-modified net-Y surfaces using density functional theory. The adsorption parameters and electronic attributes of diverse configurations have been scrutinized. Calculations indicate that net-Y exhibits limited adsorption capacity for both gases. The doped substrate exhibits a localized magnetic moment around the Fe atom, indicating the possible occurrence of the Kondo effect in the system. The substrate chemisorbs with the target gas through the Fe 3d orbitals. Additionally, after the adsorption of gases, the system undergoes a transition from metallic to semiconductor properties, accompanied by a near-complete disappearance of magnetism. Specifically, in two adsorption configurations, the systems manifest the characteristics of half-semiconductor and half-metal, respectively. Our study provides evidence that the incorporation of Fe-modified net-Y shows potential as a disposable device for detecting and purifying the decomposition products of SF<span>(_6)</span>, presenting a prospective application for net-Y in spintronic devices.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141873088","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":"Determination of the non-Euclidean lower critical dimension for the site percolation problem","authors":"P. M. Centres,&nbsp;F. Nieto","doi":"10.1140/epjb/s10051-024-00753-w","DOIUrl":"10.1140/epjb/s10051-024-00753-w","url":null,"abstract":"<p>The investigation of site percolation on Sierpinski carpets is carried out through comprehensive numerical simulations. We utilize finite- size scaling theory, staying within the constraints of our computational resources, to determine critical exponents and percolation thresholds. Moreover, we employ an approach developed by Elliot et al. (Phys Rev C 6:3185, 1994; Phys Rev C 55:1319, 1997), which streamlines the process by eliminating the necessity of dealing with large lattices. This method facilitates the extraction of critical quantities that characterize the transition from a single generation within a given structure. By implementing this procedure, we enhance efficiency and accuracy in analyzing the percolation phenomenon on Sierpinski carpets. The obtained values of the percolation thresholds are plotted as a function of the fractal dimensions in order to determine the lower critical dimension of the site percolation problem which is calculated to be <span>(d_c^L=1.52)</span>. In addition, the behavior of the critical exponents as a function of the fractal dimension is also shown and discussed.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781516","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":"Magnetohydro-convective instability in a saturated Darcy–Brinkman medium with viscous dissipation","authors":"Anil Kumar,&nbsp;D. Bhargavi,&nbsp;P. G. Siddheshwar","doi":"10.1140/epjb/s10051-024-00738-9","DOIUrl":"10.1140/epjb/s10051-024-00738-9","url":null,"abstract":"<div><p>The influence of dissipation with viscosity on magnetohydro-convective instability in a saturated Darcy–Brinkman medium is examined. The bottom boundary is designated as adiabatic, whereas the top boundary is isothermal. Numerical linear stability analysis investigates normal modes that disturb the horizontal base flow at different inclinations. The case study shows that the most unstable disturbances are horizontal rolls, normal modes characterized by a wave vector perpendicular to the main flow direction. The horizontal rolls are the favored instability mode. Barletta et al. also showed that horizontal rolls are more unstable than any other oblique roll mode in the hydromagnetic scenario. This finding provides insights into the behavior of MHD fluid flow and heat transfer in porous media, with implications for applications in geoscience, engineering, and environmental science.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><img></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781518","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":"Publisher Correction: Effects of ballistic transport on the thermal resistance and temperature profile in nanowires","authors":"R. Meyer,&nbsp;Graham W. Gibson,&nbsp;Alexander N. Robillard","doi":"10.1140/epjb/s10051-024-00744-x","DOIUrl":"10.1140/epjb/s10051-024-00744-x","url":null,"abstract":"","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjb/s10051-024-00744-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Periodic boundary condition effects in small-world networks","authors":"Yann Lucas Silva,&nbsp;Ariadne de Andrade Costa","doi":"10.1140/epjb/s10051-024-00746-9","DOIUrl":"10.1140/epjb/s10051-024-00746-9","url":null,"abstract":"<p>Understanding boundary conditions is crucial for properly modeling interactions and constraints within a system. In particular, periodic boundary conditions play an important role, because they allow systems to be treated as if existing in a continuous, constraint-free space, with significant relevance across diverse scientific fields. Our study explores the effects of periodic boundary conditions on Small-World networks by comparing traditional and flat versions derived from Ring and Line networks, respectively, through comparisons of network metrics and disconnection assessments. Recognizing the critical role of network topology in the behavior of dynamical models, we use an epidemic model to show that the structure of a network can either facilitate or hinder the spread of disease, emphasizing the importance of boundary conditions on these dynamics. The faster spread of disease in Ring networks, with shorter Average Shortest Paths, as well as their resilience on keeping network connectivity under rewiring, illustrate the impact that periodic boundary conditions can have on epidemic scenarios.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781600","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":"The effect of Mn-doping on structural, electronic, ferromagnetic, and optical properties of monolayer-WSe2 using first-principles calculations","authors":"M. S. Woldesenbet,&nbsp;N. G. Debelo,&nbsp;M. M. Woldemariam","doi":"10.1140/epjb/s10051-024-00748-7","DOIUrl":"10.1140/epjb/s10051-024-00748-7","url":null,"abstract":"<div><p>This study employs density functional theory, utilizing plane wave ultra-soft pseudopotentials (PW-USPPs) within the generalized gradient approximation (GGA) and incorporating the Hubbard potential (GGA + U), to investigate the structural, electronic, and magnetic characteristics of Mn-doped 2D—WSe₂ monolayers. The pristine WSe₂ monolayer is identified as a nonmagnetic direct band gap semiconductor with a band gap of 1.55 eV. Upon substituting Mn for W in the WSe₂ monolayer, the resulting structure exhibits enhanced stability, indicated by a negative formation energy. The Mn-doped monolayer-WSe₂ adopts a semi-metallic nature, deviating from the nonmagnetic characteristics of the pristine 2D—WSe₂, showcasing impurity bands dispersion near the Fermi level. The total magnetic moment within the nearest neighboring interactions of the Mn impurity atoms increases notably and it is attributed to the electron-correlation effect in the high spin state under the GGA + U approximation. However, this correlation effect proves insignificant on the total magnetic moment for the second nearest neighboring interactions, yielding consistent outcomes in both GGA and GGA + U approximations. The transition of ferromagnetic to antiferromagnetic states occurs within the temperature range of 400 K–450 K for low Mn-atom concentrations (below 12.5%), indicating long-range ferromagnetic ordering crucial for high-temperature 2D-diluted magnetic semiconductors. However, at high concentrations of impurity atoms, the temperature drops below room temperature (220 K in 22.2%) in the doped monolayer WSe₂, showing weak magnetic interaction. Lastly, the optical properties of the doped system is studied by applying polarization in perpendicular and parallel directions to the plane of the monolayer.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"97 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781519","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}