  The generation of entangled photon pairs which are compatible with quantum
devices and standard telecommunication channels are critical for the
development of long range fiber quantum networks. Aside from wavelength,
bandwidth matching and high fidelity of produced pairs are necessary for high
interfacing efficiency. High-rate, robust entanglement sources that satisfy all
these conditions remain an outstanding experimental challenge. In this work, we
study an entanglement source based on four-wave mixing in a diamond
configuration in a warm rubidium vapor. We theoretically and experimentally
investigate a new operating regime and demonstrate an entanglement source which
produces highly non-degenerate $795$ and $1324$-nm photon pairs. With this
source we are able to achieve in-fiber entangled pair generation rates greater
than $10^7\, /s$, orders of magnitude higher than previously reported atomic
sources. Additionally, given our source's native compatibility with telecom
infrastructure and atomic systems, it is an important step towards scalable
quantum networks.
