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arXiv · 0909.1208

Waveguide-based OPO source of entangled photon pairs

Enrico Pomarico·Bruno Sanguinetti·Nicolas Gisin·Robert Thew·Hugo Zbinden·Gerhard Schreiber·Abu Thomas·Wolfgang Sohler
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Abstract

In this paper we present a compact source of narrow-band energy-time entangled photon pairs in the telecom regime based on a Ti-indiffused Periodically Poled Lithium Niobate (PPLN) waveguide resonator, i.e. a waveguide with end-face dielectric multi-layer mirrors. This is a monolithic doubly resonant Optical Parametric Oscillator (OPO) far below threshold, which generates photon pairs by Spontaneous Parametric Down Conversion (SPDC) at around 1560nm with a 117MHz (0.91 pm)- bandwidth. A coherence time of 2.7 ns is estimated by a time correlation measurement and a high quality of the entangled states is confirmed by a Bell-type experiment. Since highly coherent energy-time entangled photon pairs in the telecom regime are suitable for long distance transmission and manipulation, this source is well suited to the requirements of quantum communication.

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Enrico Pomarico, Bruno Sanguinetti, Nicolas Gisin, Robert Thew, Hugo Zbinden, Gerhard Schreiber, Abu Thomas, Wolfgang Sohler. 2009-09-07. Waveguide-based OPO source of entangled photon pairs. https://doi.org/10.1088/1367-2630%2F11%2F11%2F113042

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