Classical spin in contact with an anomalous dissipative heat bath

Abstract

In this work, we analyze Langevin like equation of a classical spin interacting with a heat bath through momentum variables, starting from the fully dynamical Hamiltonian description. The obtained Langevin equation is non-Markovian with multiplicative noise terms. The concomitant dissipative terms obey the Fluctuation-dissipation theorem. The Markovian limit correctly produces the Kubo and Hashitsume equation. The perturbative treatment of our equations produces the Landau-Lifshitz equation. Finally, we discuss about the Fokker-Planck equation corresponding to the Langevin equations and the concept of equilibrium probability distribution is analyzed. � 2017 Author(s).