Journal of Physics A Mathematical and Theoretical

Decoherence recuperating fast environmental dynamics

Murat Çetinbaş

Published Jan 14, 2010• 0 citations

Abstract

We examine the exact internal decoherence dynamics of a qubit in an isolated Josephson charge-qubit quantum computer in the presence of one- and two-body static internal imperfections. By help of open system dynamics quantifiers, i.e. purity, fidelity, covariance and Loschmidt echo, we distinguish between non-unitary and unitary components of internal decoherence dynamics and show that the non-unitary component consists of two processes: system-environment entanglement and incoherence. Our results indicate that the incoherence process is the major source of internal decoherence rather than system-environment entanglement. We find that strong one-body intra–environmental interactions, which generate fast environmental dynamics, result in a rapid suppression of decoherence induced by both system–environment entanglement and incoherence processes. We explain the mechanisms of suppression of decoherence for these two processes and discuss our results.

DOI: 10.1088/1751-8113/43/5/055309

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