Physical Review E

Canonical formulation of quantum dissipation and noise in a generalized spin bath

Arnab Ghosh, Sudarson Sekhar Sinha, Deb Shankar Ray

Published Jul 19, 2012• 11 citations

Abstract

The quantum dynamics of a particle coupled to the dissipative degrees of freedom of a generalized spin bath in the presence of an external force field is presented. Based on Holstein-Primakoff transformation, which sets up a mapping between boson and spin operators, we show that the spin-1/2 bath and the harmonic bath can be realized as two special limits of the generalized bath. In the large spin limit, the Hamiltonian reduces to well-known Zwanzig Hamiltonian. Making use of spin coherent states and canonical thermal distributions of the associated c numbers, we derive and explore the quantum Langevin equation and the properties of the spin and harmonic baths in the context of quantum dissipation of the system.

DOI: 10.1103/physreve.86.011122

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