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When does a detector click?

Brunetti, Romeo, Klaus Fredenhagen

Published Jan 1, 2002• 1 citation
Publisher

Abstract

We propose a general construction of an observable measuring the time of occurence of an effect in quantum theory. Time delay in potential scattering is computed as a straightforward application.
DOI
10.3204/pubdb-2017-02277

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Phase-sensitive properties of light play a crucial role in a variety of quantum optical phenomena, which have been mostly discussed in the framework of photoelectric detection theory. However, modern detection schemes, such as arrays of on-off detectors, are not based on photoelectric counting. We demonstrate that the theory of homodyning with such click-counting detectors can be established by using a proper detection model. For practical applications, a variety of typically occurring imperfections are rigorously analyzed and directly observable nonclassicality criteria are studied. Fundamental examples demonstrate the general functionality of our technique. Thus, our approach of homodyne detection with on-off detector systems is able to bridge the gap between imperfect detection and the phase resolution demands for modern applications of quantum light.