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-12 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.
|Journal||Physical Review E - Statistical, Nonlinear, and Soft Matter Physics|
|State||Published - 19 Jul 2012|