Fluid viscoelasticity triggers fast transitions of a Brownian particle in a double well optical potential

Abstract

Thermally activated transitions are ubiquitous in nature, occurring in complex environments which are typically conceived as ideal viscous fluids. We report the first direct observations of a Brownian bead transiting between the wells of a bistable optical potential in a viscoelastic fluid with a single long relaxation time. We precisely characterize both the potential and the fluid, thus enabling a neat comparison between our experimental results and a theoretical model based on the generalized Langevin equation. Our findings reveal a drastic amplification of the transition rates compared to those in a Newtonian fluid, stemming from the relaxation of the fluid during the particle crossing events.

6 pages and four figures

References in corpus (5)

• Artificial Brownian motors: Controlling transport on the nanoscale
• Giant Colloidal Diffusivity on Corrugated Optical Vortices
• Omnidirectional Transport in Fully Reconfigurable Two Dimensional Optical Ratchets
• Escape of a passive particle from activity-induced energy landscape: Emergence of slow and fast effective diffusion
• Active matter in a viscoelastic environment

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