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arXiv · 1711.09992

Nine-Path Quantum Interferometry over 60 km

Batiste Galmès·Kien Phan-Huy·Luca Furfaro·Yanne K. Chembo·Jean-Marc Merolla
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Abstract

The archetypal quantum interferometry experiment yields an interference pattern that results from the indistinguishability of two spatiotemporal paths available to a photon or to a pair of entangled photons. A fundamental challenge in quantum interferometry is to perform such experiments with a higher number of paths, and over large distances. In particular, the distribution of such highly entangled states in long-haul optical fibers is one of the core concepts behind quantum information networks. We demonstrate that using indistinguishable frequency paths instead of spatiotemporal ones allows for robust, high-dimensional quantum interferometry in optical fibers. In our system, twin-photons from an Einstein-Podolsky-Rosen (EPR) pair are offered up to 9 frequency paths after propagation in long-haul optical fibers, and we show that the multi-path quantum interference patterns can be faithfully restored after the photons travel a total distance of up to 60 km.

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Batiste Galmès, Kien Phan-Huy, Luca Furfaro, Yanne K. Chembo, Jean-Marc Merolla. 2017-12-29. Nine-Path Quantum Interferometry over 60 km. https://doi.org/10.1103/physreva.99.033805

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