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arXiv · 1505.07895

Continuous variable entanglement on a chip

Genta Masada·Kazunori Miyata·Alberto Politi·Toshikazu Hashimoto·Jeremy L. O'Brien·Akira Furusawa
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Abstract

Encoding quantum information in continuous variables (CV)---as the quadrature of electromagnetic fields---is a powerful approach to quantum information science and technology. CV entanglement---light beams in Einstein-Podolsky-Rosen (EPR) states---is a key resource for quantum information protocols; and enables hybridisation between CV and single photon discrete variable (DV) qubit systems. However, CV systems are currently limited by their implementation in free-space optical networks: increased complexity, low loss, high-precision alignment and stability, as well as hybridisation, demand an alternative approach. Here we show an integrated photonic implementation of the key capabilities for CV quantum technologies---generation and characterisation of EPR beams in a photonic chip. Combined with integrated squeezing and non-Gaussian operation, these results open the way to universal quantum information processing with light.

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Genta Masada, Kazunori Miyata, Alberto Politi, Toshikazu Hashimoto, Jeremy L. O'Brien, Akira Furusawa. 2015-05-29. Continuous variable entanglement on a chip. https://doi.org/10.1038/nphoton.2015.42

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