Mid-Infrared Photon-Pair Generation in AgGaS$_2$

TL;DR

This paper demonstrates mid-infrared photon-pair generation using AgGaS$_2$ crystals via spontaneous parametric down conversion, enabling new quantum imaging and sensing applications in the mid-infrared range.

Contribution

It introduces a novel method for non-degenerate photon-pair generation in AgGaS$_2$, with tunable phase matching over a broad spectral range.

Findings

Generated idler photons above 6 μm wavelength

Achieved broad spectral bandwidth for photon pairs

Demonstrated phase matching over a large spectral range

Abstract

We demonstrate non-degenerate photon-pair generation by spontaneous parametric down conversion in a silver gallium sulfide AgGaS$_2$ crystal. By tuning the pump wavelength, we achieve phase matching over a large spectral range. This allows to generate idler photons in the mid-infrared spectral range above 6 $\mu m$ wavelength with corresponding signal photons in the visible. Also, we show photon pair generation with broad spectral bandwidth. These results are a valuable step towards the development of quantum imaging and sensing techniques in the mid-infrared.