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arXiv · 1805.06059

Violating Bell inequalities with entangled optical frequency combs and multi-pixel homodyne detection

Abstract

We have theoretically investigated the possibility of using any of several continuous-variable Bell-type inequalities - for which the dichotomic measurements are achieved with coarse-grained quadrature (homodyne) measurements - in a multi-party configuration where each participant is given a section, in the frequency domain, of the output of an optical parametric oscillator which has been synchronously-pumped with a frequency comb. Such light sources are undergoing intense study due to their novel properties, including the potential for production of light entangled in many hundreds of physical modes - a critical component for many proposals in optical or hybrid-optical quantum computation proposals. The situation we study notably uses only highly-efficient optical homodyne detection, meaning that in such systems the fair-sampling loophole would be relatively easy to avoid.

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William N. Plick, Francesco Arzani, Nicolas Treps, Eleni Diamanti, Damian Markham. 2018-05-15. Violating Bell inequalities with entangled optical frequency combs and multi-pixel homodyne detection. https://doi.org/10.1103/physreva.98.062101

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