Physical review. B, Condensed matter

Degenerate spin-boson system

Yang Chen, Ticheng Li

Published Aug 1, 1989• 4 citations

Abstract

The temporal evolution of a degenerate two-level system (spin) coupled to a dissipative bath (bosons) is studied in this Rapid Communication. Closed-form expressions for the occupancy probabilities and correlation functions are found by functional methods. The non-Markovian characteristics such as explicit dependence on the initial condition and a possible long-time tail behavior are shown to be present. We also suggest a reasonable procedure for the construction of the Green's function of the nondegenerate system.

DOI: 10.1103/physrevb.40.2712

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