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arXiv · 1603.08451

Heralded single-photon source utilizing highly nondegenerate, spectrally factorable spontaneous parametric downconversion

Fumihiro Kaneda·Karina Garay-Palmett·Alfred B. U'Ren·Paul G. Kwiat
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Abstract

We report on the generation of an indistinguishable heralded single-photon state, using highly nondegenerate spontaneous parametric downconversion (SPDC). Spectrally factorable photon pairs can be generated by incorporating a broadband pump pulse and a group-velocity matching (GVM) condition in a periodically-poled potassium titanyl phosphate (PPKTP) crystal. The heralding photon is in the near IR, close to the peak detection efficiency of off-the-shelf Si single-photon detectors; meanwhile, the heralded photon is in the telecom L-band where fiber losses are at a minimum. We observe spectral factorability of the SPDC source and consequently high purity (90%) of the produced heralded single photons by several different techniques. Because this source can also realize a high heralding efficiency (> 90%), it would be suitable for time-multiplexing techniques, enabling a pseudo-deterministic single-photon source, a critical resource for optical quantum information and communication technology.

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Fumihiro Kaneda, Karina Garay-Palmett, Alfred B. U'Ren, Paul G. Kwiat. 2016-03-28. Heralded single-photon source utilizing highly nondegenerate, spectrally factorable spontaneous parametric downconversion. https://doi.org/10.1364/oe.24.010733

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