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Continuous quantum measurement with independent detector cross-correlations

Andrew N. Jordan·Markus Buttiker
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Abstract

We investigate the advantages of using two independent, linear detectors for continuous quantum measurement. For single-shot quantum measurement, the measurement is maximally efficient if the detectors are twins. For weak continuous measurement, cross-correlations allow a violation of the Korotkov-Averin bound for the detector's signal-to-noise ratio. A vanishing noise background provides a nontrivial test of ideal independent quantum detectors. We further investigate the correlations of non-commuting operators, and consider possible deviations from the independent detector model for mesoscopic conductors coupled by the screened Coulomb interaction.

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Andrew N. Jordan, Markus Buttiker. 2005-05-02. Continuous quantum measurement with independent detector cross-correlations. https://doi.org/10.1103/physrevlett.95.220401

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