High spectral brightness telecom compatible bichromatic entanglement source using warm atomic vapors

Here, we present a high spectral brightness source of bichromatic, polarization entangled photons, based on spontaneous four-wave-mixing in a warm rubidium vapor. The source produces pairs with one of the photons in the telecom O-band, making it natively compatible with existing telecom infrastructure, and the other at 795-nm, near-resonant with the rubidium D1 line. Our source improves the entangled pair generation rate using a warm vapor by two orders of magnitude while maintaining high heralding efficiency, making it an ideal candidate for large scale telecom quantum networking demonstrations.