English

Unusual stationary state in Brownian systems with Lorentz force

Statistical Mechanics 2020-07-01 v2 Soft Condensed Matter

Abstract

In systems with overdamped dynamics, the Lorentz force reduces the diffusivity of a Brownian particle in the plane perpendicular to the magnetic field. The anisotropy in diffusion implies that the Fokker-Planck equation for the probabiliy distribution of the particle acquires a tensorial coefficient. The tensor, however, is not a typical diffusion tensor due to the antisymmetric elements which account for the fact that Lorentz force curves the trajectory of a moving charged particle. This gives rise to unusual dynamics with features such as additional Lorentz fluxes and a nontrivial density distribution, unlike a diffusive system. The equilibrium properties are, however, unaffected by the Lorentz force. Here we show that by stochastically resetting the Brownian particle, a nonequilibrium steady state can be created which preserves the hallmark features of dynamics under Lorentz force. We then consider a minimalistic example of spatially inhomogeneous magnetic field, which shows how Lorentz fluxes fundamentally alter the boundary conditions giving rise to an unusual stationary state.

Keywords

Cite

@article{arxiv.2004.04471,
  title  = {Unusual stationary state in Brownian systems with Lorentz force},
  author = {Iman Abdoli and Hidde Derk Vuijk and Rene Wittmann and Jens-Uwe Sommer and Joseph Michael Brader and Abhinav Sharma},
  journal= {arXiv preprint arXiv:2004.04471},
  year   = {2020}
}
R2 v1 2026-06-23T14:45:24.451Z