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Global stability criterion for a quantum feedback control process on a single qubit and exponential stability in case of perfect detection efficiency

Andreas de Vries
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Abstract

Quantum feedback control is a technology which can be used to drive a quantum system into a predetermined eigenstate. In this article, sufficient conditions for the experiment parameters of a quantum feedback control process of a homodyne QND measurement are given to guarantee feedback control of a spin-1/2 quantum system in case of imperfect detection efficiency. For the case of pure states and perfect detection efficiency, time scales of feedback control processes are calculated.

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Andreas de Vries. 2007-01-14. Global stability criterion for a quantum feedback control process on a single qubit and exponential stability in case of perfect detection efficiency. https://doi.org/10.1103/physreva.75.032101

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