  Bright, polarized, and high-purity single-photon sources in telecom
wavelengths are crucial components in long-distance quantum communication,
optical quantum computation and quantum networks. Semiconductor InAs/InP
quantum dots (QDs) combined with photonic cavities provide a competitive path
leading to optimal single-photon sources in this range. Here, we demonstrate a
bright and polarized single-photon source operating in the telecom C-band based
on an elliptical Bragg grating (EBG) cavity. With a significant Purcell
enhancement of 5.25$\pm$0.05, the device achieves a polarization ratio of
0.986, single-photon purity of g^2 (0)=0.078$\pm$0.016 and single-polarized
photon collection efficiency of ~ 24% at the first lens (NA=0.65) without
blinking. These findings suggest that C-band QD-based single-photon sources are
potential candidates for advancing quantum communication.
