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Modulation of dephasing due to a spin-boson environment

E. Paladino·M. Sassetti·G. Falci
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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.

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E. Paladino, M. Sassetti, G. Falci. 2004-12-22. Modulation of dephasing due to a spin-boson environment. https://doi.org/10.1016/j.chemphys.2003.08.027

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