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arXiv · 1203.6128

Optimal control for non-Markovian open quantum systems

Bin Hwang·Hsi-Sheng Goan
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Abstract

An efficient optimal-control theory based on the Krotov method is introduced for a non-Markovian open quantum system with a time-nonlocal master equation in which the control parameter and the bath correlation function are correlated. This optimal-control method is developed via a quantum dissipation formulation that transforms the time-nonlocal master equation to a set of coupled linear time-local equations of motion in an extended auxiliary Liouville space. As an illustration, the optimal-control method is applied to find the control sequences for high-fidelity Z gates and identity gates of a qubit embedded in a non-Markovian bath. Z gates and identity gates with errors less than 10^{-5} for a wide range of bath decoherence parameters can be achieved for the non-Markovian open qubit system with control over only the σz term. The control-dissipation correlation and the memory effect of the bath are crucial in achieving the high-fidelity gates.

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Bin Hwang, Hsi-Sheng Goan. 2012-03-28. Optimal control for non-Markovian open quantum systems. https://doi.org/10.1103/physreva.85.032321

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