Single photon frequency conversion for frequency multiplexed quantum networks in the telecom band

TL;DR

This paper demonstrates an integrated quantum frequency conversion protocol in the telecom band, enabling efficient, low-noise conversion between wavelength channels for quantum networks, facilitating long-distance quantum communication.

Contribution

It introduces a cascaded second order nonlinear interaction for high-efficiency, low-noise frequency conversion suitable for quantum networks and quantum memories.

Findings

Conversion efficiency of 55% with 8% uncertainty

Noise subtracted HOM dip visibility of 84.5%

Potential for interfacing broad frequency spectrum with quantum memories

Abstract

High-speed long-range quantum communication requires combining frequency multiplexed photonic channels with quantum memories. We experimentally demonstrate an integrated quantum frequency conversion protocol that can convert between wavelength division multiplexing channels in the telecom range with an efficiency of $55\pm 8\%$ and a noise subtracted HOM dip visibility of 84.5%. This protocol is based on a cascaded second order nonlinear interaction and can be used to interface a broad spectrum of frequencies with narrowband quantum memories, or alternatively as a quantum optical transponder, efficiently interfacing different regions of a frequency-multiplexed spectrum.