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arXiv · 1211.2885

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

Nobuyuki Matsuda·Hanna Le Jeannic·Hiroshi Fukuda·Tai Tsuchizawa·William John Munro·Kaoru Shimizu·Koji Yamada·Yasuhiro Tokura·Hiroki Takesue
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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 \pm 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.

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Nobuyuki Matsuda, Hanna Le Jeannic, Hiroshi Fukuda, Tai Tsuchizawa, William John Munro, Kaoru Shimizu, Koji Yamada, Yasuhiro Tokura, Hiroki Takesue. 2012-11-13. A monolithically integrated polarization entangled photon pair source on a silicon chip. https://doi.org/10.1038/srep00817

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