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arXiv · 2010.12740

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

Brandon R. Ferrer·Juan Ruben Gomez-Solano·Alejandro V. Arzola
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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.

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Brandon R. Ferrer, Juan Ruben Gomez-Solano, Alejandro V. Arzola. 2020-10-24. Fluid viscoelasticity triggers fast transitions of a Brownian particle in a double well optical potential. https://doi.org/10.1103/physrevlett.126.108001

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