Spectrally multiplexed heralded single photon source at telecom-band

TL;DR

This paper demonstrates a spectrally multiplexed heralded single photon source at telecom wavelengths, significantly improving photon rate and purity through spectral multiplexing and active manipulation, advancing scalable quantum communication.

Contribution

It introduces a novel spectral multiplexing technique with active feed-forward control to enhance heralded single photon sources at telecom wavelengths.

Findings

Spectral multiplexing erases frequency correlations in the photon pair source.

Heralded single photon rate is significantly improved while maintaining low g^{(2)}(0).

High indistinguishability demonstrated via Hong-Ou-Mandel interference.

Abstract

Heralded single photon source (HSPS) is an important way in generating genuine single photon, having advantages of experimental simplicity and versatility. However, HSPS intrinsically suffers from the trade-off between the heralded single photon rate and the single photon purity. To overcome this, one can apply multiplexing technology in different degrees of freedom to enhance the performance of HSPS. Here, by employing spectral multiplexing and active feed-forward spectral manipulating, we demonstrate a HSPS at 1.5 {\mu}m telecom-band. Our experimental results show that the spectral multiplexing effectively erases the frequency correlation of pair source and significantly improves the heralded single photon rate while keeping the g{^(^2^)}(0) as low as 0.0006{\pm}0.0001. The Hong-Ou-Mandel interference between the heralded single photons and photons from an independent weak coherent source indicates a high indistinguishability. Our results pave a way for scalable HSPS by spectral multiplexing towards deterministic single photon emission.