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Continuous weak measurement and feedback control of a solid-state charge qubit: physical unravelling of non-Lindblad master equation

Shi-Kuan Wang·Jinshuang Jin·Xin-Qi Li
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Abstract

Conventional quantum trajectory theory developed in quantum optics is largely based on the physical unravelling of Lindbald-type master equation, which constitutes the theoretical basis of continuous quantum measurement and feedback control. In this work, in the context of continuous quantum measurement and feedback control of a solid-state charge qubit, we present a physical unravelling scheme of non-Lindblad type master equation. Self-consistency and numerical efficiency are well demonstrated. In particular, the control effect is manifested in the detector noise spectrum, and the effect of measurement voltage is discussed.

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Shi-Kuan Wang, Jinshuang Jin, Xin-Qi Li. 2006-11-20. Continuous weak measurement and feedback control of a solid-state charge qubit: physical unravelling of non-Lindblad master equation. https://doi.org/10.1103/physrevb.75.155304

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