Communications Physics最新文献_第6页

Modified Born series with virtual absorbing boundary enabling large-scale electromagnetic simulation 带虚拟吸收边界的修正博恩级数，实现大规模电磁模拟

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-25 DOI: 10.1038/s42005-024-01882-5

Pinxuan He, Jiamin Liu, Honggang Gu, Hao Jiang, Shiyuan Liu

{"title":"Modified Born series with virtual absorbing boundary enabling large-scale electromagnetic simulation","authors":"Pinxuan He, Jiamin Liu, Honggang Gu, Hao Jiang, Shiyuan Liu","doi":"10.1038/s42005-024-01882-5","DOIUrl":"10.1038/s42005-024-01882-5","url":null,"abstract":"Numerical electromagnetic field solvers are significant for nanophotonic and photoelectronic technology, especially for computational imaging, metasurface, and biomedical microscopy, in which large-scale simulations serve as the core. Conventionally, these simulations use absorbing boundary conditions (ABC) to simulate open-domain systems. However, the existing ABCs require large memory to sufficiently suppress reflection at boundaries, which is prohibitive for large-scale applications. This work proposes a virtual absorbing boundary condition based on the angular spectrum method (ASM) to reduce the memory usage of ABC. The ASM is used to cover the polluted field in the boundary region, which eliminates the need to store the field in the boundary region. Combined with the Fourier transforms-based modified Born series, memory usage can be reduced to a level close to the theoretical limit. This proposed method offers a substantial boost for applications related to large-scale simulations and memory-constrained devices like GPU. This work proposes a virtual boundary condition based on the angular spectrum method to reduce memory usage in electromagnetic simulations, which eliminates the need to store the field in the boundary region. Combined with the Fourier transforms-based modified Born series, memory usage can be reduced to a level close to the theoretical limit.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-8"},"PeriodicalIF":5.4,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01882-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Quantifying the in-plane strain influence on second harmonic generation of molybdenum disulfide 量化面内应变对二硫化钼二次谐波产生的影响

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-24 DOI: 10.1038/s42005-024-01877-2

Huadan Xing, Jibin Liu, Zihao Zhao, Xiaoyong He, Wei Qiu

{"title":"Quantifying the in-plane strain influence on second harmonic generation of molybdenum disulfide","authors":"Huadan Xing, Jibin Liu, Zihao Zhao, Xiaoyong He, Wei Qiu","doi":"10.1038/s42005-024-01877-2","DOIUrl":"10.1038/s42005-024-01877-2","url":null,"abstract":"Quantifying the strain, and even the strain state, is critical for the advancement of strain engineering in microelectronics and optoelectronics fields, whether using the classical semiconductors or emerging two-dimensional materials. Second Harmonic Generation (SHG) has emerged as a potent technique for exploring the optical-mechanical properties of two-dimensional transition metal dichalcogenides (2D-TMDCs). Based on the theoretical framework of SHG, this work analyses the mechanism of different strain states acting on the SHG polarization-intensity spectrum (PIS) of MoS2. A quantifying method is proposed by establishing the analytic relationship between the in-plane strain components and the petal amplitude ratios (PARs) obtained from detected PIS. After calibrating the key parameters of MoS2 SHG PIS, a series of biaxial and uniaxial tensile experiments are performed, whose results are mostly agreed with the theoretical expectations, thus verifying the reliability, correctness and universality of the proposed method for quantitively characterizing the strain state of monolayer MoS2. Second Harmonic Generation (SHG) is potent for exploring the optical-mechanical properties of two-dimensional transition metal dichalcogenides. This work presents a method to quantify the strain state influence on the SHG polarization-intensity spectrum of MoS2, and the reliability of proposed method is verified by numerical and physical experiments.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-10"},"PeriodicalIF":5.4,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01877-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Exploring the potential of self-pulsing optical microresonators for spiking neural networks and sensing 探索自脉冲光学微谐振器在尖峰神经网络和传感方面的潜力。

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-22 DOI: 10.1038/s42005-024-01869-2

Stefano Biasi, Alessio Lugnan, Davide Micheli, Lorenzo Pavesi

{"title":"Exploring the potential of self-pulsing optical microresonators for spiking neural networks and sensing","authors":"Stefano Biasi, Alessio Lugnan, Davide Micheli, Lorenzo Pavesi","doi":"10.1038/s42005-024-01869-2","DOIUrl":"10.1038/s42005-024-01869-2","url":null,"abstract":"Photonic platforms are promising for implementing neuromorphic hardware due to their high processing speed, low power consumption, and ability to perform parallel processing. A ubiquitous device in integrated photonics, which has been extensively employed for the realization of optical neuromorphic hardware, is the microresonator. The ability of CMOS-compatible silicon microring resonators to store energy enhances the nonlinear interaction between light and matter, enabling energy efficient nonlinearity, fading memory and the generation of spikes via self-pulsing. In the self-pulsing regime, a constant input signal can be transformed into a time-dependent signal based on pulse sequences. Previous research has shown that self-pulsing enables the microresonator to function as an energy-efficient artificial spiking neuron. Here, we extend the experimental study of single and coupled microresonators in the self-pulsing regime to confirm their potential as building blocks for scalable photonic spiking neural networks. Furthermore, we demonstrate their potential for introducing all-optical long-term memory and event detection capabilities into integrated photonic neural networks. In particular, we show all-optical long-term memory up to at least 10 μs and detection of input spike rates, which is encoded into different stable self-pulsing dynamics. While silicon photonics is an attractive platform for neuromorphic computing, it generally lacks scalable nodes that provide nonlinearity and memory. Here, the authors show experimentally that simple and compact networks of silicon microring resonators exhibit complex self-pulsing responses that can be exploited for all-optical long-term memory and sensing.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-10"},"PeriodicalIF":5.4,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11584396/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142709489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Mechanism of magnetic phase transition in correlated magnetic metal: insight into itinerant ferromagnet Fe3−δGeTe2 相关磁性金属的磁性相变机制：对巡回铁磁体 Fe3-δGeTe2 的启示

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-22 DOI: 10.1038/s42005-024-01874-5

Yuanji Xu, Yue-Chao Wang, Xintao Jin, Haifeng Liu, Yu Liu, Haifeng Song, Fuyang Tian

{"title":"Mechanism of magnetic phase transition in correlated magnetic metal: insight into itinerant ferromagnet Fe3−δGeTe2","authors":"Yuanji Xu, Yue-Chao Wang, Xintao Jin, Haifeng Liu, Yu Liu, Haifeng Song, Fuyang Tian","doi":"10.1038/s42005-024-01874-5","DOIUrl":"10.1038/s42005-024-01874-5","url":null,"abstract":"Developing a comprehensive magnetic theory for correlated itinerant magnets poses challenges due to the difficulty in reconciling both local moments and itinerant electrons. In this work, we investigate the microscopic process of magnetic phase transition in ferromagnetic metal Fe3−δGeTe2. We find that Hund’s coupling is crucial for establishing ferromagnetic order. During the ferromagnetic transition, we observe the formation of quasiparticle flat bands and an opposing tendency in spectral weight transfer, primarily between the lower and upper Hubbard bands, across the two spin channels. Moreover, our results indicate that one of the inequivalent Fe sites exhibits Mott physics, while the other Fe site exhibits Hund’s physics, attributable to their distinct atomic environments. We suggest that ferromagnetic order reduces spin fluctuations and makes flat bands near the Fermi level more distinct. The hybridization between the distinctly flat bands and other itinerant bands offers a possible way to form heavy fermion behavior in ferromagnets. The complex interactions of competing orders drive correlated magnetic metals to a new frontier for discovering outstanding quantum states. Understanding magnetism in correlated itinerant systems has been an important yet challenging task due to the complex interplay among Hund, Mott, and Kondo physics. In this work, by using DFT + DMFT, the authors reveal the mechanism of the magnetic phase transition and the heavy-fermion behavior in low temperatures in a ferromagnetic metal, shedding light on the roles of the above three factors.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-8"},"PeriodicalIF":5.4,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01874-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Directed motion of cognitive active agents in a crowded three-way intersection 拥挤的三叉路口中认知型主动代理的定向运动

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-22 DOI: 10.1038/s42005-024-01860-x

Priyanka Iyer, Rajendra Singh Negi, Andreas Schadschneider, Gerhard Gompper

{"title":"Directed motion of cognitive active agents in a crowded three-way intersection","authors":"Priyanka Iyer, Rajendra Singh Negi, Andreas Schadschneider, Gerhard Gompper","doi":"10.1038/s42005-024-01860-x","DOIUrl":"10.1038/s42005-024-01860-x","url":null,"abstract":"Understanding the navigation through semi-dense crowds at intersections poses a significant challenge in pedestrian dynamics, with implications for facility design and insights into emergent collective behavior. To tackle this problem, a system of cognitive active agents at a crowded three-way intersection is studied using Langevin simulations of intelligent active Brownian particles (iABPs) with directed visual perception (resulting in non-reciprocal interactions) and self-steering avoidance—without volume exclusion. We find that the emergent self-organization depends on agent maneuverability, goal fixation, and vision angle, and identify several forms of collective behavior, including localized flocking, jamming and percolation, and self-organized rotational flows. Additionally, we demonstrate that the motion of individual agents can be characterized by fractional Brownian motion and Lévy walk models across different parameter regimes. Moreover, despite the rich variety of collective behavior, the fundamental flow diagram shows a universal curve for different vision angles. Our research highlights the impact of collision avoidance, goal following, and vision angle on the individual and collective dynamics of interacting pedestrians. The study of self-organisation of pedestrian movement at crossing is important for the design of strategies facilitating pedestrian flow in crowded areas and the mitigation of crowd-related accidents. The authors study the motion of pedestrians using a model inspired from active matter systems finding interesting phases of three interacting streams of agents, including jamming, and the emergence of a vortex state.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-11"},"PeriodicalIF":5.4,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01860-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Evolutionary dynamics in stochastic nonlinear public goods games 随机非线性公共产品博弈中的进化动力学

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-21 DOI: 10.1038/s42005-024-01865-6

Wenqiang Zhu, Xin Wang, Chaoqian Wang, Longzhao Liu, Jiaxin Hu, Zhiming Zheng, Shaoting Tang, Hongwei Zheng, Jin Dong

{"title":"Evolutionary dynamics in stochastic nonlinear public goods games","authors":"Wenqiang Zhu, Xin Wang, Chaoqian Wang, Longzhao Liu, Jiaxin Hu, Zhiming Zheng, Shaoting Tang, Hongwei Zheng, Jin Dong","doi":"10.1038/s42005-024-01865-6","DOIUrl":"10.1038/s42005-024-01865-6","url":null,"abstract":"Understanding the evolution of cooperation in multi-player games is of vital significance for natural and social systems. An important challenge is that group interactions often lead to nonlinear synergistic effects. However, previous models mainly focus on deterministic nonlinearity, where synergy or discounting effects occur under specific conditions, not accounting for uncertainty and stochasticity in real-world systems. Here, we develop a probabilistic framework to study the cooperative behavior in stochastic nonlinear public goods games. Through both analytical treatment and Monte Carlo simulations, we provide a comprehensive understanding of social dilemmas with stochastic nonlinearity in both well-mixed and structured populations. We find that increasing the degree of nonlinearity makes synergy more advantageous when competing with discounting, thereby promoting cooperation. Furthermore, we show that network reciprocity loses effectiveness when the probability of synergy is small. Moreover, group size exhibits nonlinear effects on group cooperation regardless of the underlying structure. Our findings thus provide insights into how stochastic nonlinearity influences the emergence of prosocial behavior. Cooperation in multi-player games is influenced by nonlinear interactions and randomness found in natural and social systems. The authors develop a probabilistic framework and find that stronger nonlinear effects enhance cooperation by boosting the collective benefits of working together, and that network reciprocity loses effectiveness when synergistic interactions are rare.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-10"},"PeriodicalIF":5.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01865-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Using continuation methods to analyse the difficulty of problems solved by Ising machines 用延续方法分析伊辛机解决问题的难度

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-21 DOI: 10.1038/s42005-024-01867-4

Jacob Lamers, Guy Verschaffelt, Guy Van der Sande

{"title":"Using continuation methods to analyse the difficulty of problems solved by Ising machines","authors":"Jacob Lamers, Guy Verschaffelt, Guy Van der Sande","doi":"10.1038/s42005-024-01867-4","DOIUrl":"10.1038/s42005-024-01867-4","url":null,"abstract":"Ising machines are dedicated hardware solvers of NP-hard optimization problems. However, they do not always find the most optimal solution. The probability of finding this optimal solution depends on the problem at hand. Using continuation methods, we show that this is closely linked to how the ground state emerges from other states when a system parameter is changed, i.e. its bifurcation sequence. From this analysis, we can determine the effectiveness of solution schemes. Moreover, we find that the proper choice of implementation of the Ising machine can drastically change this bifurcation sequence and therefore vastly increase the probability of finding the optimal solution. Lastly, we also show that continuation methods themselves can be used directly to solve optimization problems. An Ising machine is a piece of hardware that tries to solve quadratic unconstrained binary optimization problems. The authors explain why some problems are significantly easier to tackle than others using Ising machines and demonstrate that different physical implementations can render some challenging problems a lot easier to solve.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-11"},"PeriodicalIF":5.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01867-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Topological transition in filamentous cyanobacteria: from motion to structure 丝状蓝藻的拓扑转变：从运动到结构

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-20 DOI: 10.1038/s42005-024-01866-5

Jan Cammann, Mixon K. Faluweki, Nayara Dambacher, Lucas Goehring, Marco G. Mazza

{"title":"Topological transition in filamentous cyanobacteria: from motion to structure","authors":"Jan Cammann, Mixon K. Faluweki, Nayara Dambacher, Lucas Goehring, Marco G. Mazza","doi":"10.1038/s42005-024-01866-5","DOIUrl":"10.1038/s42005-024-01866-5","url":null,"abstract":"Many active systems are capable of forming intriguing patterns at scales significantly larger than the size of their individual constituents. Cyanobacteria are one of the most ancient and important phyla of organisms that has allowed the evolution of more complex life forms. Despite its importance, the role of motility on the pattern formation of their colonies is not understood. Here, we investigate the large-scale collective effects and rich dynamics of gliding filamentous cyanobacteria colonies, while still retaining information about the individual constituents’ dynamics and their interactions. We investigate both the colony’s transient and steady-state dynamics and find good agreement with experiments. We furthermore show that the Péclet number and aligning interaction strength govern the system’s topological transition from an isotropic distribution to a state of large-scale reticulate patterns. Although the system is topologically non-trivial, the parallel and perpendicular pair correlation functions provide structural information about the colony, and thus can be used to extract information about the early stages of biofilm formation. Finally, we find that the effects of the filaments’ length cannot be reduced to a system of interacting points. Our model proves to reproduce both cyanobacteria colonies and systems of biofilaments where curvature is transported by motility. Active matter systems can spontaneously form structure. Using concepts of nonequilibrium statistical physics and experiments, this work demonstrates the existence of a topological transition in filamentous cyanobacteria colonies from an isotropic distribution to dense bundles organized in a reticulate pattern.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-12"},"PeriodicalIF":5.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01866-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142672792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Benchmarking the optimization of optical machines with the planted solutions 用植入式解决方案优化光学设备的基准

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-19 DOI: 10.1038/s42005-024-01870-9

Nikita Stroev, Natalia G. Berloff, Nir Davidson

{"title":"Benchmarking the optimization of optical machines with the planted solutions","authors":"Nikita Stroev, Natalia G. Berloff, Nir Davidson","doi":"10.1038/s42005-024-01870-9","DOIUrl":"10.1038/s42005-024-01870-9","url":null,"abstract":"This research focuses on developing effective benchmarks for quadratic unconstrained binary optimization instances, crucial for evaluating the performance of Ising hardware and solvers. Currently, the field lacks accessible and reproducible models for systematically testing such systems, particularly in terms of detailed phase space characterization. Here, we introduce universal generative models based on an extension of Hebb’s rule of associative memory with asymmetric pattern weights. We conduct comprehensive calculations across different scales and dynamical equations, examining outcomes like the probabilities of reaching the ground state, planted state, spurious state, or other energy levels. Additionally, the generated problems reveal properties such as the easy-hard-easy complexity transition and complex solution cluster structures. This method offers a promising platform for analyzing and understanding the behavior of physical hardware and its simulations, contributing to future advancements in optimization technologies. The authors present a method for creating generative models that produce test instances for quadratic unconstrained binary optimization (QUBO) problems, inspired by Hebb’s rule. Their approach identifies key solution patterns and complexity transitions, providing a platform to evaluate the performance of Ising hardware and solvers efficiently.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-9"},"PeriodicalIF":5.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01870-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142672771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0

Spontaneous flows and quantum analogies in heterogeneous active nematic films 异质活性向列薄膜中的自发流动和量子相似性

IF 5.4 1区物理与天体物理

Communications Physics Pub Date : 2024-11-19 DOI: 10.1038/s42005-024-01864-7

Alexander J. H. Houston, Nigel J. Mottram

{"title":"Spontaneous flows and quantum analogies in heterogeneous active nematic films","authors":"Alexander J. H. Houston, Nigel J. Mottram","doi":"10.1038/s42005-024-01864-7","DOIUrl":"10.1038/s42005-024-01864-7","url":null,"abstract":"Incorporating the inherent heterogeneity of living systems into models of active nematics is essential to provide a more realistic description of biological processes such as bacterial growth, cell dynamics and tissue development. Spontaneous flow of a confined active nematic is a fundamental feature of these systems, in which the role of heterogeneity has not yet been considered. We therefore determine the form of spontaneous flow transition for an active nematic film with heterogeneous activity, identifying a correspondence between the unstable director modes and solutions to Schrödinger’s equation. We consider both activity gradients and steps between regions of distinct activity, finding that such variations can change the signature properties of the flow. The threshold activity required for the transition can be raised or lowered, the fluid flux can be reduced or reversed and interfaces in activity induce shear flows. In a biological context fluid flux influences the spread of nutrients while shear flows affect the behaviour of rheotactic microswimmers and can cause the deformation of biofilms. All the effects we identify are found to be strongly dependent on not simply the types of activity present in the film but also on how they are distributed. Incorporating the inherent heterogeneity of living systems into models of active nematics is essential to provide a realistic description of important biological processes. The authors determine the form of spontaneous flow transition for a heterogeneous active nematic film, finding a correspondence with Schrodinger’s equation and changes to signature properties of the flow and transition threshold.","PeriodicalId":10540,"journal":{"name":"Communications Physics","volume":" ","pages":"1-9"},"PeriodicalIF":5.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s42005-024-01864-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142672779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}

引用次数: 0