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Controlling a mesoscopic spin environment by quantum bit manipulation

J. M. Taylor·A. Imamoglu·M. D. Lukin
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Abstract

We present a unified description of cooling and manipulation of a mesoscopic bath of nuclear spins via coupling to a single quantum system of electronic spin (quantum bit). We show that a bath cooled by the quantum bit rapidly saturates. Although the resulting saturated states of the spin bath (``dark states'') generally have low degrees of polarization and purity, their symmetry properties make them a valuable resource for the coherent manipulation of quantum bits. Specifically, we demonstrate that the dark states of nuclear ensembles can be used to coherently control the system-bath interaction and to provide a robust, long-lived quantum memory for qubit states.

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J. M. Taylor, A. Imamoglu, M. D. Lukin. 2003-08-22. Controlling a mesoscopic spin environment by quantum bit manipulation. https://doi.org/10.1103/physrevlett.91.246802

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