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arXiv · 2010.06214

Proposal and Proof-of-Principle Demonstration of Fast-Switching Broadband Frequency-Shifting for a Frequency-Multiplexed Quantum Repeater

Peng-Cheng Wang·Oriol Pietx-Casas·Mohsen Falamarzi Askarani·Gustavo Castro do Amaral
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Abstract

A proposal for fast-switching broadband frequency-shifting technology making use of frequency conversion in a nonlinear crystal is set forth, whereby the shifting is imparted to the converted photons by creating a bank of frequency-displaced pump modes that can be selected by a photonic switch and directed to the nonlinear crystal. Proof-of-principle results show that the expected frequency-shifting operation can be achieved. Even though the dimensions of the currently employed crystal and significant excess loss in the experimental setup prevented conversion of single-photon-level inputs, thorough experimental and theoretical analysis of the noise contribution allowed for the estimation of the system performance in an optimized scenario, where the expected signal-to-noise ratio for single-photon conversion and frequency-shifting can reach up to 25 dB with proper narrow-band filtering and state-of-the-art devices. The proposed frequency-shifting solution figures as a promising candidate for applications in frequency-multiplexed quantum repeater architectures with 25 dB output SNR (with 20\% conversion efficiency) and capacity for 16 channels spread around a 100 GHz spectral region.

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Peng-Cheng Wang, Oriol Pietx-Casas, Mohsen Falamarzi Askarani, Gustavo Castro do Amaral. 2020-10-13. Proposal and Proof-of-Principle Demonstration of Fast-Switching Broadband Frequency-Shifting for a Frequency-Multiplexed Quantum Repeater. https://doi.org/10.1364/josab.412517

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