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arXiv · 2009.00255

Ultra-fast Hong-Ou-Mandel interferometry via temporal filtering

Yoshiaki Tsujimoto·Kentaro Wakui·Mikio Fujiwara·Masahide Sasaki·Masahiro Takeoka
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Abstract

Heralded single photons (HSPs) generated by spontaneous parametric down-conversion (SPDC) are useful resource to achieve various photonic quantum information processing. Given a large-scale experiment which needs multiple HSPs, increasing the generation rate with suppressing higher-order pair creation is desirable. One of the promising ways is to use a pump laser with a GHz-order repetition rate. In such a high repetition rate regime, however, single-photon detectors can only partially identify the pulses. Hence, we develop a simple model to consider that effect on the spectral purity, and experimentally demonstrate a high-visibility Hong-Ou-Mandel interference between two independent HSPs generated by SPDC with 3.2 GHz-repetition-rate mode-locked pump pulses. The observed visibility of 0.88(3) is in good agreement with our theoretical model.

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Yoshiaki Tsujimoto, Kentaro Wakui, Mikio Fujiwara, Masahide Sasaki, Masahiro Takeoka. 2020-09-01. Ultra-fast Hong-Ou-Mandel interferometry via temporal filtering. https://doi.org/10.1364/oe.430502

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