Fluctuation theorem of a mesoscopic engine and spin switching

Research paper by Yasuhiro Utsumi, Tomohito Taniguchi

Indexed on: 04 Dec '16Published on: 02 Dec '16Published in: Fortschritte der Physik


Based on the fluctuation theorem of a small engine, we present a description of the stochastic dynamics of a mesoscopic system. We apply it to the problem of the escape of a particle from a metastable state subjected to a fluctuating nonconservative force, which is beyond the description of the fluctuation-dissipation theorem. As an example, we consider a reversal of a small magnetic moment by fluctuating spin-torque. The joint probability distribution of input heat and output work is derived from the full-counting statistics under adiabatic pumping. We predict a threshold voltage above which the spin-torque shot noise induces probabilistic switching events, and below which such events are blocked.