Decoherence in two-state quantun systems through an external controllable driving field without rotating wave approximation

Abstract

Abstract:

The problem of the decoherence of two-state quantum systems interacting with a bath through an external controllable driving field without rotating wave approximation is discussed. The off-diagonal elements of the density operator in two-state quantum systems are obtained. The result reflects that the decoherence of the two-state quantum systems has something to do with its original state, frequency of the bath and frequency of the external controllable driving field. The relation between the decoherence and external controllable driving field is studied. Properties of an external controllable driving field are obtained when the two-state quantum systems of coherence is maintained.

Key words: quantum optics, decoherence, without rotating wave approximation, two-state quantum systems, external controllable driving field

CLC Number:

O431.2

ZHANG Cheng-qiang, JI Chang-jian, LIU Meng, TAN Xia, LI Hua. Decoherence in two-state quantun systems through an external controllable driving field without rotating wave approximation[J]. J4, 2011, 28(6): 705-709.

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