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Ultrafast initialization and QND-readout of a spin qubit via control of nanodot-vacuum coupling

Ren-Bao Liu·Wang Yao·L. J. Sham
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Abstract

Ultrafast initialization enables fault-tolerant processing of quantum information while QND readout enables scalable quantum computation. By spatially assembling photon resonators and wave-guides around an n-doped nanodot and by temporally designing optical pump pulses, an efficient quantum pathway can be established from an electron spin to a charged exciton to a cavity photon and finally to a flying photon in the waveguide. Such control of vacuum-nanodot coupling can be exploited for ultrafast initialization and QND readout of the spin, which are particularly compatible with the optically driven spin quantum computers.

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Ren-Bao Liu, Wang Yao, L. J. Sham. 2004-08-06. Ultrafast initialization and QND-readout of a spin qubit via control of nanodot-vacuum coupling. https://doi.org/10.1103/physrevb.72.081306

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