Stochastic thermodynamics of macrospins with fluctuating amplitude and direction

Bandopadhyay, S and Chaudhuri, Debasish and Jayannavar, A M (2015) Stochastic thermodynamics of macrospins with fluctuating amplitude and direction. Physical Review E, 92 (032143). ISSN 1539-3755

Full text not available from this repository. (Request a copy)

Abstract

We consider stochastic energy balance and entropy production (EP) in a generalized Langevin dynamics of macrospins, allowing for both amplitude and direction fluctuations, under external magnetic field. EP is calculated using a Fokker-Planck equation, distinguishing between reversible and irreversible parts of probability currents. The system entropy increases due to irreversible non-equilibrium processes, and reduces as heat dissipates to the surrounding environment. Using path probability distributions of time-forward trajectories and conjugate trajectories under time reversal, we obtain fluctuation theorems (FT) for total stochastic EP. We show that the choice of conjugate trajectories is crucial in obtaining entropy-like quantities that obey FTs.

[error in script]

IITH Creators: