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arXiv:1704.03213 · Physical Review Applied

Generation of Path-Encoded Greenberger-Horne-Zeilinger States

Nicola Bergamasco, M. Menotti, John E. Sipe, Marco Liscidini

Published Nov 8, 2017• 27 citations
arXivHTMLPDF

Abstract

The ability to generate states of light with specific quantum correlations is very important in quantum communication and computation. While this ability has been realized in bulk optics, most approaches implemented so far are not suitable for the integrated photonic circuits that are expected to revolutionize quantum photonics in the near future. This work shows that, by using the path-encoding representation, one can generate entangled Greenberger-Horne-Zeilinger states in an integrated device. This approach is scalable and compatible with several platforms, from laser-written devices to silicon photonics.

DOI
10.1103/physrevapplied.8.054014

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We propose a scheme to probabilistically generate Greenberger–Horne–Zeilinger states encoded on the path degree of freedom of three photons. These photons are totally independent from each other, having no direct interaction during the whole evolution of the protocol, which remarkably requires only linear optical devices to work and two extra ancillary photons to mediate the correlation. The efficacy of the method, which has potential application in distributed quantum computation and multiparty quantum communication, is analyzed in comparison with similar proposals reported in the recent literature. We also discuss the main error sources that limit the efficiency of the protocol in a real experiment and some interesting aspects about the mediator photons in connection with the concept of spatial nonlocality.
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