Journal of Applied Physics

Non-Markovian effects in dissipative flux qubits with time-dependent magnetic fields and partial-collapse quantum measurements

Zheng-Da Hu, Xu Jingbo, Ye-Qi Zhang

Published Nov 4, 2013• 0 citations

Abstract

We investigate the effects of the time-dependent magnetic field (TDMF) and partial-collapse quantum measurements (PCQMs) on the information flow of a superconducting flux qubit coupled to a reservoir and find that the information flow is equivalent to the quantum Fisher information flow in the resonant case. A scheme is proposed to preserve the quantum correlations of two uncoupled flux qubits interacting with independent reservoirs via PCQMs and TDMFs, and steady amount of entanglement can be achieved by the PCQMs. We also discuss the effect of TDMF on the dynamics of the entanglement and show distinct behaviors in the Markovian and non-Markovian regimes. Finally, we explore the influence of non-Markovian effect on the dynamics of entanglement under the combined action of TDMFs and PCQMs and show that the combined action of TDMFs and PCQMs can protect entanglement better for some situations.

DOI: 10.1063/1.4828735

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