  Large-scale quantum networks rely on optical fiber networks and photons as
so-called flying qubits for information transport. While dispersion and
absorption of optical fibers are minimum at the infrared telecom wavelengths,
most atomic and solid state platforms operate at visible or near-infrared
wavelengths. Quantum frequency conversion is required to bridge these two
wavelength regimes, and nonlinear crystals are currently employed for this
process. Here, we report on a novel approach of frequency conversion to the
telecom band. This interaction is based on coherent Stokes Raman scattering
(CSRS), a four-wave mixing process resonantly enhanced in a dense molecular
hydrogen gas. We show the conversion of photons from \SI{863}{\nano\meter} to
the telecom O-Band and demonstrate that the input polarization state is
preserved. This process is intrinsically broad-band and can be adapted to any
other wavelength.
