Active particles bound by information flows

Khadka, Utsab; Holubec, Viktor; Yang, Han‐Kwang; Cichos, Frank

doi:10.1038/s41467-018-06445-1

Cited by 136 publications

(169 citation statements)

References 42 publications

Supporting

Mentioning

166

Contrasting

Order By: Relevance

“…(32) becomes equal to the result for the planar interface, Eq. (22). The concentration inside the cluster needs to exceed the thresholdc with c(r c ) =c at the boundary, which constitutes our third condition.…”

Section: Circular Clustersmentioning

confidence: 99%

“…Phoretic colloidal particles provide a well-characterized experimental model system in which we can study different aspects of emerging collective behavior [19]. Implementing responses beyond excluded volume and alignment requires control over particles motion [20][21][22]. For phoretic Janus particles triggered by light, individual control of motility has been demonstrated recently for two modes of perception: cohesive flocking through vision cones [23] and for quorum sensing [24].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Quorum-sensing active particles with discontinuous motility

2020

View full text Add to dashboard Cite

We develop a dynamic mean-field theory for polar active particles that interact through a selfgenerated field, in particular one generated through emitting a chemical signal. While being a form of chemotactic response, it is different from conventional chemotaxis in that particles discontinuously change their motility when the local concentration surpasses a threshold. The resulting coupled equations for density and polarization are linear and can be solved analytically for simple geometries, yielding inhomogeneous density profiles. Specifically, here we consider a planar and circular interface. Our theory thus explains the observed coexistence of dense aggregates with an active gas. There are, however, differences to the more conventional picture of liquid-gas coexistence based on a free energy, most notably the absence of a critical point. We corroborate our analytical predictions by numerical simulations of active particles under confinement and interacting through volume exclusion. Excellent quantitative agreement is reached through an effective translational diffusion coefficient. We finally show that an additional response to the chemical gradient direction is sufficient to induce vortex clusters. Our results pave the way to engineer motility responses in order to achieve aggregation and collective behavior even at unfavorable conditions. arXiv:1909.12758v1 [cond-mat.stat-mech]

show abstract

Section: Circular Clustersmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Quorum-sensing active particles with discontinuous motility

2020

View full text Add to dashboard Cite

show abstract

“…In a phenomenological top-down approach, (physical) interactions are deduced from observations [270,271]. Alternatively, in a bottom-up approach, the effect of complex information processing strategies of individual agents, e.g., delayed signal processing, is studied [272][273][274]. Collective behavior can even emerge from a purely probabilistic approach by considering intrinsic motivation and maximization of future options via processing of sensed information, without any a priori specification of social forces or individual interaction rules [273,275].…”

Section: Animal Groupsmentioning

confidence: 99%

Computational models for active matter

et al. 2020

View full text Add to dashboard Cite

A variety of computational models have been developed to describe active matter at different length and time scales. The diversity of the methods and the challenges in modeling active matterranging from molecular motors and cytoskeletal filaments over artificial and biological swimmers on microscopic to groups of animals on macroscopic scales-mainly originate from their out-ofequilibrium character, multiscale nature, nonlinearity, and multibody interactions. In the present review, various modeling approaches and numerical techniques are addressed, compared, and differentiated to illuminate the innovations and current challenges in understanding active matter. The complexity increases from minimal microscopic models of dry active matter toward microscopic models of active matter in fluids. Complementary, coarse-grained descriptions and continuum models are elucidated. Microscopic details are often relevant and strongly affect collective behaviors, which implies that the selection of a proper level of modeling is a delicate choice, with simple models emphasizing universal properties and detailed models capturing specific features. Finally, current approaches to further advance the existing models and techniques to cope with real-world applications, such as complex media and biological environments, are discussed.2

show abstract

“…Furthermore, they are argued to be closely related to the mechanism of robustness in biological systems [18,19].On another front, active matter, a collection of self-driven particles, has attracted much interest as an ideal platform to study biological physics [20][21][22] and out-of-equilibrium statistical physics [23][24][25][26][27][28]. While a prototype of active matter has been originally introduced to understand animal flocking behavior [29,30], recent experimental developments have allowed one to manipulate and observe artificial active systems in a controlled manner by utilizing Janus particles [31], catalytic colloids [32] and external feedback control [33].The aim of this Letter is to show that a topologically nontrivial feature can ubiquitously emerge in a nonequilibrium steady state of active matter and demonstrate it by analyzing the concrete minimal model, which can be realized with current experimental techniques. Specifically, we first point out that the net vorticity of the steady-state flow must vanish under realistic conditions for active systems in the continuum space.…”

mentioning

confidence: 99%

Anomalous Topological Active Matter

Sone

Ashida

2019

Phys. Rev. Lett.

View full text Add to dashboard Cite

Active systems exhibit spontaneous flows induced by self-propulsion of microscopic constituents and can reach to a nonequilibrium steady state without an external drive. Constructing the analogy between the quantum anomalous Hall insulators and active matter with spontaneous flows, we show that topologically protected sound modes can arise in a steady-state active system in the continuum space. We point out that the net vorticity of the steady-state flow, which acts as a counterpart of the gauge field in condensed-matter settings, must vanish under realistic conditions for active systems. As a consequence, the quantum anomalous Hall effect naturally provides design principles for realizing topological metamaterials. We propose and analyze the concrete minimal model and numerically calculate its band structure and eigenvectors, demonstrating the emergence of nonzero bulk topological invariants with the corresponding edge sound modes. This new type of topological active systems can potentially expand possibilities for their experimental realizations and may have broad applications to practical active metamaterials. Possible realization of non-Hermitian topological phenomena in active systems is also discussed.Topologically nontrivial bands, which have been at the forefront of condensed matter physics [1][2][3][4][5][6], can also appear in various classical systems such as photonic [7-10] and phononic systems [11][12][13][14][15][16][17]. Such topologically nontrivial systems exhibit unidirectional modes that propagate along the edge of a sample and are immune to disorder. The existence of edge modes originates from the nontrivial topology characterized by bulk topological invariants of underlying photonic or acoustic band structures. The topological edge modes give rise to novel functionalities potentially applicable to, e.g., sonar detection and heat diodes [11,15]. Furthermore, they are argued to be closely related to the mechanism of robustness in biological systems [18,19].On another front, active matter, a collection of self-driven particles, has attracted much interest as an ideal platform to study biological physics [20][21][22] and out-of-equilibrium statistical physics [23][24][25][26][27][28]. While a prototype of active matter has been originally introduced to understand animal flocking behavior [29,30], recent experimental developments have allowed one to manipulate and observe artificial active systems in a controlled manner by utilizing Janus particles [31], catalytic colloids [32] and external feedback control [33].The aim of this Letter is to show that a topologically nontrivial feature can ubiquitously emerge in a nonequilibrium steady state of active matter and demonstrate it by analyzing the concrete minimal model, which can be realized with current experimental techniques. Specifically, we first point out that the net vorticity of the steady-state flow must vanish under realistic conditions for active systems in the continuum space. Since the vorticity in active matter can act as a counterpart o...

show abstract

Active particles bound by information flows

Cited by 136 publications

References 42 publications

Quorum-sensing active particles with discontinuous motility

Quorum-sensing active particles with discontinuous motility

Computational models for active matter

Anomalous Topological Active Matter

Contact Info

Product

Resources

About