International Conference on Quantum Information

Coherence stability for a three-level system

Luis Roa, A. Krügel

Published Jan 1, 2007• 0 citations

Abstract

We have found, for a specific model of interaction, an expression which allows us to estimate the time scale order of magnitude for which the decoherence instability of a quantum state is onset. We study the stability of the coherence of a pure state for a three level quantum system under the effect of an interaction with a set of boson systems and driven by two Raman classical fields. Evaluating the order of magnitude of the decoherence time scale and assuming the boson systems to be in thermal states, we find for a symmetric V -system a set of three states stable against decoherence and, for a symmetric cascade-system we find a bidimensional subspace whose states are stable against the considered decoherence mechanism.

DOI: 10.1364/icqi.2007.jwc52

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