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arXiv · 1110.3734

Generalised Einstein Relation for Hot Brownian Motion

D. Chakraborty·M. V. Gnann·D. Rings·J. Glaser·F. Otto·F. Cichos·K. Kroy
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Abstract

The Brownian motion of a hot nanoparticle is described by an effective Markov theory based on fluctuating hydrodynamics. Its predictions are scrutinized over a wide temperature range using large-scale molecular dynamics simulations of a hot nanoparticle in a Lennard-Jones fluid. The particle positions and momenta are found to be Boltzmann distributed according to distinct effective temperatures $T_\mathrm{HBM}$ and $T_\mathrm{k}$ . For $T_\mathrm{HBM}$ we derive a formally exact theoretical prediction and establish a generalised Einstein relation that links it to directly measurable quantities.

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D. Chakraborty, M. V. Gnann, D. Rings, J. Glaser, F. Otto, F. Cichos, K. Kroy. 2011-10-17. Generalised Einstein Relation for Hot Brownian Motion. https://doi.org/10.1209/0295-5075%2F96%2F60009

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