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arXiv:1912.11154 · Physical Review Applied

Versatile Photonic Entanglement Synthesizer in the Spatial Domain

David Barral, Mattia Walschaers, Kamel Bencheikh, Valentina Parigi, Juan Ariel Levenson, Nicolas Treps, Nadia Belabas

Published Oct 15, 2020• 17 citations
arXivHTMLPDF

Abstract

Multimode entanglement is an essential resource for quantum information in continuous-variable systems. Light-based quantum technologies will arguably not be built upon table-top bulk setups, but will presumably rather resort to integrated optics. Sequential bulk opticslike proposals based on cascaded integrated interferometers are not scalable with the current state-of-the-art low-loss materials used for continuous variables. We analyze the multimode continuous-variable entanglement capabilities of a compact currently available integrated bulk-optics analog: the array of nonlinear waveguides. We theoretically demonstrate that this simple and compact structure, together with a reconfigurable input pump distribution and multimode coherent detection of the output modes, is a versatile entanglement synthesizer in the spatial domain. We exhibit this versatility through analytical and numerically optimized multimode squeezing, entanglement, and cluster-state generation in different encodings. Our results re-establish spatial encoding as a contender in the game of continuous-variable quantum information processing.

DOI
10.1103/physrevapplied.14.044025

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