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arXiv · 0907.0469

Nonequilibrium noise in electrophoresis: the microion wind

Suropriya Saha·Sriram Ramaswamy
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Abstract

We analyze theoretically the dynamics of a single colloidal particle in an externally applied electric field. The thermal motions of microions lead to an anisotropic, nonequilibrium source of noise, pro- portional to the field, in the effective Langevin equation for the colloid. The fluctuation-dissipation ratio depends strongly on frequency, and the colloid if displaced from its steady-state position relaxes with a velocity not proportional to the gradient of the logarithm of the steady-state probability.

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Suropriya Saha, Sriram Ramaswamy. 2009-07-02. Nonequilibrium noise in electrophoresis: the microion wind. https://arxiv.org/abs/0907.0469

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