Enhanced directionality of active processes in a viscoelastic bath

Biswajit Das; Shuvojit Paul; Sreekanth K. Manikandan; Ayan Banerjee

doi:10.1088/1367-2630/acfb31

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arXiv · 2302.01996

Enhanced directionality of active processes in a viscoelastic bath

Biswajit Das·Shuvojit Paul·Sreekanth K. Manikandan·Ayan Banerjee

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Abstract

Active fluctuations are known to play a significant role in the intracellular transport of passive objects. However, the effect of viscoelasticity of the environment in shaping such processes is relatively less understood. Here, with a minimal experiment using a driven colloid in a viscoelastic bath, we show that viscoelasticity significantly increases the mean injected power to the passive object ($\sim 50\%$ compared to a viscous medium), for the same strength of the external driving. Additionally, we observe a notable reduction in negative work fluctuations across a wide range of driving amplitudes. These findings collectively suggest an enhanced directionality in driven processes within a viscoelastic bath, which we attribute to the emergence of interactions between the colloid and the viscoelastic medium.

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Biswajit Das, Shuvojit Paul, Sreekanth K. Manikandan, Ayan Banerjee. 2023-02-03. Enhanced directionality of active processes in a viscoelastic bath. https://doi.org/10.1088/1367-2630/acfb31

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