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arXiv · 2207.14706

Ultratunable quantum frequency conversion in photonic crystal fiber

K. A. G. Bonsma-Fisher·P. J. Bustard·C. Parry·T. A. Wright·D. G. England·B. J. Sussman·P. J. Mosley
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Abstract

Quantum frequency conversion of single photons between wavelength bands is a key enabler to realizing widespread quantum networks. We demonstrate the quantum frequency conversion of a heralded 1551 nm photon to any wavelength within an ultrabroad (1226 - 1408 nm) range in a group-velocity-symmetric photonic crystal fiber (PCF), covering over 150 independent frequency bins. The target wavelength is controlled by tuning only a single pump laser wavelength. We find internal, and total, conversion efficiencies of 12(1)% and 1.4(2)%, respectively. For the case of converting 1551 nm to 1300 nm we measure a heralded $g^{(2)}(0) = 0.25(6)$ for converted light from an input with $g^{(2)}(0) = 0.034(8)$. We expect that this PCF can be used for a myriad of quantum networking tasks.

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K. A. G. Bonsma-Fisher, P. J. Bustard, C. Parry, T. A. Wright, D. G. England, B. J. Sussman, P. J. Mosley. 2022-07-29. Ultratunable quantum frequency conversion in photonic crystal fiber. https://doi.org/10.1103/physrevlett.129.203603

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