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arXiv:1211.2885 · Scientific Reports

A monolithically integrated polarization entangled photon pair source on a silicon chip

Nobuyuki Matsuda, Hanna Le Jeannic, Hiroshi Fukuda, Tai Tsuchizawa, William J. Munro, Kaoru Shimizu, Koji Yamada, 康弘都倉, Hiroki Takesue

Published Nov 12, 2012• 167 citations

Abstract

Integrated photonic circuits are one of the most promising platforms for large-scale photonic quantum information systems due to their small physical size and stable interferometers with near-perfect lateral-mode overlaps. Since many quantum information protocols are based on qubits defined by the polarization of photons, we must develop integrated building blocks to generate, manipulate, and measure the polarization-encoded quantum state on a chip. The generation unit is particularly important. Here we show the first integrated polarization-entangled photon pair source on a chip. We have implemented the source as a simple and stable silicon-on-insulator photonic circuit that generates an entangled state with 91 ± 2% fidelity. The source is equipped with versatile interfaces for silica-on-silicon or other types of waveguide platforms that accommodate the polarization manipulation and projection devices as well as pump light sources. Therefore, we are ready for the full-scale implementation of photonic quantum information systems on a chip.

DOI: 10.1038/srep00817

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