Probing the Fluctuation-Dissipation Theorem in a Perrin-like Experiment
arXiv:1712.01733 · doi:10.1103/PhysRevLett.107.130601
Abstract
In this Letter, we present a new experimental approach to investigate the effective temperature concept as a generalization of the fluctuation-dissipation theorem (FDT) for nonequilibrium systems. Simultaneous measurements of diffusion coefficient and sedimentation velocity of heavy colloids, embedded in a Laponite clay suspension, are performed with a fluorescence-recovery-based setup. This nonperturbative dual measurement, performed at a single time in a single sample, allows for a direct application of the FDT to the tracer velocity observable. It thus provides a well-defined derivation of the effective temperature in this ageing colloidal gel. For a wide range of concentrations and ageing times, we report no violation of the FDT, with effective temperature agreeing with bath temperature. This result is consistent with recent theoretical predictions on the coupling between the velocity observable and nonequilibrium gels dynamics.
References in corpus (20)
- Analytical Solution of the Off-Equilibrium Dynamics of a Long Range Spin-Glass Model
- Energy flow, partial equilibration and effective temperatures in systems with slow dynamics
- Nonequilibrium dynamics and fluctuation-dissipation relation in a sheared fluid
- Restoring a fluctuation-dissipation theorem in a nonequilibrium steady state
- Two-time scales, two-temperature scenario for nonlinear rheology
- Observation of Fluctuation-Dissipation-Theorem Violations in a Structural Glass
- Fluctuation-dissipation ratio of a spin glass in the aging regime
- Routes to gelation in a clay suspension
- Probing an nonequilibrium Einstein relation in an aging colloidal glass
- Fluctuation dissipation ratio in an aging Lennard-Jones glass
- Experimental observation of the intricate free-energy landscape for a soft glassy system
- Competing interactions in arrested states of colloidal clays
- Intermittency in aging
- Fluctuation-dissipation theorem in an aging colloidal glass
- Experimental study of the Fluctuation-Dissipation-Relation during an aging process
- Measurement of Effective Temperatures in an Aging Colloidal Glass
- Generalized fluctuation-dissipation relation and effective temperature in off-equilibrium colloids
- Experimental study of out of equilibrium fluctuations in a colloidal suspension of Laponite using optical traps
- Effective temperatures from the fluctuation-dissipation measurements in soft glassy materials
- Dependence of the fluctuation-dissipation temperature on the choice of observable