Modulation of dephasing due to a spin-boson environment
arXiv:cond-mat/0412615 · doi:10.1016/j.chemphys.2003.08.027
Abstract
We study the reduced dynamics of a spin (qubit) coupled to a spin-boson environment in the case of pure dephasing. We derive formal exact expressions which can be cast in terms of exact integro-differential master equations. We present results for a SB environment with ohmic dissipation at finite temperatures. For the special value of the ohmic damping strength K=1/2 the reduced dynamics is found in analytic form. For K<<1 we discuss the possibility of modulating the effect of the SB environment on the qubit. In particular we study the effect of the crossover to a slow environment dynamics, which may be triggered by changing both the temperature and the system-environment coupling.
16 pages, 2 figures, Chemical Physics special issue on the Spin-Boson problem, edited by H. Grabert and A. Nitzan