Mechanism of barrier crossing dynamics in the presence of both time dependent and independent magnetic fields

TL;DR

This paper investigates how combined static and fluctuating magnetic fields influence the barrier crossing dynamics of a Brownian particle, revealing complex behaviors including resonance effects and non-monotonic rate variations.

Contribution

It introduces a detailed mechanism explaining the effects of magnetic fields on barrier crossing, highlighting the interplay of induced electric fields and resonance phenomena.

Findings

Magnetic coupling can induce resonance-like effects.

Increasing magnetic field strength reduces the barrier crossing rate.

Fluctuating magnetic fields activate particles via induced electric fields.

Abstract

In this paper we have presented the mechanism of the barrier crossing dynamics of a Brownian particle which is coupled to a thermal bath in the presence of both time independent and fluctuating magnetic fields. Here the following three aspects are important in addition to the role of the thermal bath on the barrier crossing dynamics. Magnetic field induced coupling may introduce a resonance like effect. Another role of the field is that enhancement of its strength reduces the frequency factor of the barrier crossing rate constant. Finally, the fluctuating magnetic field introduces an induced electric field which activates the Brownian particle to cross the energy barrier. As a result of interplay among these aspects versatile non-monotonic behavior may appear in the variation of the rate constant as a function of the strength of the time independent magnetic field.