Demonstration of 2.1 photon-per-bit sensitivity for BPSK at 9.94-Gb/s with rate-½ FEC. - David J. Geisler; Timothy M. Yarnall; William E. Keicher; Mark L. Stevens; Andrew M. Fletcher; Ronald R. Parenti; David O. Caplan; Scott A. Hamilton (OFC/NFOEC, 2013)