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Single-photon quantum nondemolition detectors constructed with linear optics and projective measurements

Pieter Kok·Hwang Lee·Jonathan P. Dowling
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Abstract

Optical quantum nondemolition devices can provide essential tools for quantum information processing. Here, we describe several optical interferometers that signal the presence of a single photon in a particular input state without destroying it. We discuss both entanglement-assisted and non-entanglement-assisted interferometers, with ideal and realistic detectors. We found that existing detectors with 88% quantum efficiency and single-photon resolution can yield output fidelities of up to 89%, depending on the input state. Furthermore, we construct expanded protocols to perform QND detections of single photons that leave the polarization invariant. For detectors with 88% efficiency we found polarization-preserving output fidelities of up to 98.5%.

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Pieter Kok, Hwang Lee, Jonathan P. Dowling. 2003-01-23. Single-photon quantum nondemolition detectors constructed with linear optics and projective measurements. https://doi.org/10.1103/physreva.66.063814

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