Synchronization of coupled active rotators by common noise

活性物质同步与协同学

Active matter synchronization and synergetics

本研究通过随机智能体模型，发现活性物质在关键能量供应和合作生产下，经平均场耦合可实现同步振荡，体现协同学中的自发秩序涌现。

Active hydrodynamics of synchronization and ordering in moving oscillators

The nature of emergent collective behaviors of moving physical agents interacting with their neighborhood is a long-standing open issue in physical and biological systems alike. This calls for studies on the control of synchronization and the degree of order in a collection of diffusively moving noisy oscillators. We address this by constructing a generic hydrodynamic theory for active phase fluctuations in a collection of large number of nearly phase-coherent moving oscillators in two dimensions. Our theory describes the general situation where phase fluctuations and oscillator mobility mutua…

Activity induced synchronization: From Mutual Flocking to Chiral Self-Sorting

Synchronization, the temporal coordination of coupled oscillators, allows fireflies to flash in unison, neurons to fire collectively and human crowds to fall in step on the London Millenium bridge. Here, we interpret active (or self-propelled) chiral microswimmers with a distribution of intrinsic frequencies as motile oscillators and show that they can synchronize over very large distances, even for local coupling in 2D. This opposes to canonical non-active oscillators on static or time-dependent networks, leading to synchronized domains only. A consequence of this activity-induced synchroniza…

Patterns of synchronization in the hydrodynamic coupling of active colloids

A system of active colloidal particles driven by harmonic potentials to oscillate about the vertices of a regular polygon, with hydrodynamic coupling between all particles, is described by a piece-wise linear model which exhibits various patterns of synchronization. Analytical solutions are obtained for this class of dynamical systems. Depending only on the number of particles, the synchronization occurs into states in which nearest neighbors oscillate either in-phase, or anti-phase, or in phase-locked (time-shifted) trajectories.

Emergent Synchronization and Flocking in Purely Repulsive Self-Navigating Particles

Inspired by groups of animals and robots, we study the collective dynamics of large numbers of active particles, each one trying to get to its own randomly placed target, while avoiding collisions with each other. The particles we study are repulsive homing active Brownian particles (HABPs) - self-propelled particles whose orientation relaxes at a finite rate towards an absorbing target in $2d$ continuous space. For a wide range of parameters, these particles form synchronised system-wide chiral flocks, in spite of the absence of explicit alignment interactions. We show that this dramatic beha…

非互易活性极性混合物中的同步与例外点

Synchronization and exceptional points in nonreciprocal active polar mixtures

本文研究非互易活性极性混合物，通过跨尺度分析揭示非互易性导致粒子手性运动及从同步团簇到嵌合态的多样行为，并发现手性在例外点对应耦合强度处达到峰值。

Collective states of active matter with stochastic reversals: emergent chiral states and spontaneous current switching

We study collective dynamical behavior of active particles with topological interactions and directional reversals. Surprising phenomena are shown to emerge as the interaction relaxation time is varied relative to the reversal rate, such as spontaneous formation of collective chiral states due to phase synchronization, and collective directional reversals in the presence of confinement. The results have a direct relevance to modelling and understanding collective reversals and synchronization phenomena in active matter.

Synchronization and Collective Dynamics in a Carpet of Microfluidic Rotors

We study synchronization of an array of rotors on a substrate that are coupled by hydrodynamic interaction. The rotors that are modeled by an effective rigid body, are driven by an internal torque and exerts an active force on the surrounding fluid. The long-ranged nature of the hydrodynamic interaction between the rotors causes a rich pattern of dynamical behaviors including phase ordering and turbulent spiral waves. The model provides a novel example of coupled oscillators with long-range interaction. Our results suggest strategies for designing controllable microfluidic mixers using the eme…

活性量子自旋的非互易同步

Nonreciprocal Synchronization of Active Quantum Spins

本文提出两种量子自旋通过手性波导实现吸引-排斥型非互易相互作用的模型，证明在热力学极限下可导致宇称-时间对称性自发破缺的时间晶体行波态，并通过连续监测输出场在有限系统中实现量子行波态。

Nonequilibrium thermodynamics of coupled molecular oscillators: The energy cost and optimal design for synchronization

A model of coupled molecular oscillators is proposed to study nonequilibrium thermodynamics of synchronization. We find that synchronization of nonequilibrium oscillators costs energy even when the oscillator-oscillator coupling is conservative. By solving the steady state of the many-body system analytically, we show that the system goes through a nonequilibrium phase transition driven by energy dissipation, and the critical energy dissipation depends on both the frequency and strength of the exchange reactions. Moreover, our study reveals the optimal design for achieving maximum synchronizat…

活性物质群体振荡器中的运动性诱导相分离与阻挫

Motility Induced Phase Separation and Frustration in Active Matter Swarmalators

本研究引入弹性相互作用的游动-翻转活性圆盘群体振荡器系统，发现内部相位相互作用可产生多种活性相，包括阻挫MIPS态和超晶格MIPS态。

Synchronization in A Carpet of Hydrodynamically Coupled Rotors with Random Intrinsic Frequency

We investigate synchronization caused by long-range hydrodynamic interaction in a two-dimensional, substrated array of rotors with random intrinsic frequencies. The rotor mimics a flagellated bacterium that is attached to the substrate ("bacterial carpet") and exerts an active force on the fluid. Transition from coherent to incoherent regimes is studied numerically, and the results are compared to a mean-field theory. We show that quite a narrow distribution of the intrinsic frequency is required to achieve collective motion in realistic cases. The transition is gradual, and the critical behav…

Non-universal results induced by diversity distribution in coupled excitable systems

We consider a system of globally coupled active rotators near the excitable regime. The system displays a transition to a state of collective firing induced by disorder. We show that this transition is found generically for any diversity distribution with well defined moments. Singularly, for the Lorentzian distribution (widely used in Kuramoto-like systems) the transition is not present. This warns about the use of Lorentzian distributions to understand the generic properties of coupled oscillators.