Evaluating linear response in active systems with no perturbing field

Abstract

We present a method for the evaluation of time-dependent linear response functions for systems of active Ornstein-Uhlenbeck particles from unperturbed simulations. The method is inspired by the Malliavin weights sampling method proposed by Warren and Allen [Phys. Rev. Lett. 109, 250601 (2012)] for systems of Brownian particles. We illustrate our method by evaluating a linear response function for a single active particle in an external harmonic potential. As an application, we calculate the time-dependent mobility function and an effective temperature, defined through the Einstein relation between the self-diffusion and mobility coefficients, for a system of active particles interacting via a screened-Coulomb potential. We find that this effective temperature decreases with increasing persistence time of the self-propulsion. Initially, for not too large persistence times, it changes rather slowly, but then it decreases markedly when the persistence length of the self-propelled motion becomes comparable with the particle size.

Final version accepted in EPL

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Cited by in corpus (29)

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• Perspective: Nonequilibrium glassy dynamics in dense systems of active particles
• The Entropy Production of Ornstein-Uhlenbeck Active Particles: a path integral method for correlations
• How active forces influence nonequilibrium glass transitions
• Nonequilibrium mode-coupling theory for dense active systems of self-propelled particles
• Linear response theory and Green-Kubo relations for active matter
• Effective temperatures in inhomogeneous passive and active bidimensional Brownian particle systems
• On the Fluctuation-Dissipation Relation in non-equilibrium and non-Hamiltonian systems
• Active matter: quantifying the departure from equilibrium
• How irreversible are steady-state trajectories of a trapped active particle?
• Effective equilibrium states in mixtures of active particles driven by colored noise
• Critical active dynamics is captured by a colored-noise driven field theory
• Irreversibility in active matter: General framework for active Ornstein-Uhlenbeck particles
• Response of active Brownian particles to shear flow
• Generalized Fluctuation-Dissipation relations holding in non-equilibrium dynamics
• How to define temperature in active systems?
• Anomalous mobility of a driven active particle in a steady laminar flow
• The Many Faces of Fluctuation-Dissipation Relations Out of Equilibrium
• Tagged active particle: probability distribution in a slowly varying external potential is determined by effective temperature obtained from the Einstein relation
• Brownian systems perturbed by mild shear: Comparing response relations
• A handy fluctuation-dissipation relation to approach generic noisy systems and chaotic dynamics
• Transmission of mobility via cooperative mechanisms in soft active matter
• Confined active particles with spatially dependent Lorentz force: an odd twist to the "best Fokker-Planck approximation"
• Dynamic phase transition induced by active molecules simulating a facilitation mechanism in a supercooled liquid
• Effective Energy, Interactions And Out Of Equilibrium Nature Of Scalar Active Matter
• A facilitation-induced fluidization transition in supercooled water triggered by a few active molecules