Absolute negative mobility induced by thermal equilibrium fluctuations

TL;DR

This paper reports the discovery of absolute negative mobility in inertial Brownian particles within symmetric potentials, induced by thermal fluctuations or deterministic dynamics, and proposes experimental verification using Josephson junctions.

Contribution

It introduces a new transport phenomenon called absolute negative mobility induced by thermal equilibrium fluctuations and deterministic dynamics in symmetric systems.

Findings

Thermal fluctuations induce ANM in tailored parameter regimes.

ANM occurs against small bias in symmetric potentials.

Experimental setup with Josephson junctions can verify the phenomenon.

Abstract

A novel transport phenomenon is identified that is induced by inertial Brownian particles which move in simple one-dimensional, symmetric periodic potentials under the influence of both a time periodic and a constant, biasing driving force. Within tailored parameter regimes, thermal equilibrium fluctuations induce the phenomenon of absolute negative mobility (ANM), which means that the particle noisily moves {\it backwards} against a small constant bias. When no thermal fluctuations act, the transport vanishes identically in these tailored regimes. There also exist parameter regimes, where ANM can occur in absence of fluctuations on grounds which are rooted solely in the complex, inertial deterministic dynamics. The experimental verification of this new transport scheme is elucidated for the archetype symmetric physical system: a convenient setup consisting of a resistively and capacitively shunted Josephson junction device.