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arXiv · 2504.08993

Spectral compression of single-photon wave packets by sum-frequency conversion in slow-light waveguides

Michael G. Raymer
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Abstract

A slow-light scheme is proposed for simultaneous frequency conversion and spectral compression of a weak optical pulse, which may be in any quantum state including a single-photon state. Such a process plays crucial roles in a number of schemes for constructing quantum networks. Assuming that appropriate slow-light waveguides can be fabricated, theoretical modeling shows that a 3-ps pulse can be converted by sum-frequency generation into a pulse with duration in the ns regime with a corresponding spectral compression factor of the order of 1000 and a useful intrinsic efficiency up to 83%. Independent of the input pulse shape, the converted pulse will have a near-exponential rising shape, which is suitable for temporal-mode matching into an optical cavity.

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Michael G. Raymer. 2025-04-11. Spectral compression of single-photon wave packets by sum-frequency conversion in slow-light waveguides. https://arxiv.org/abs/2504.08993

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