Opt Lett. 2026 Jun 1;51(11):3253-3256. doi: 10.1364/OL.592295.
ABSTRACT
This work investigates the enhancement of channel capacity in photon-starved deep-space optical links by leveraging inter-photon correlations. We analyze an M-ary pulse-position modulation (PPM) photon-counting channel in the presence of Poisson background noise and compare conventional signal sources with recently proposed correlated photonic-dimer sources. In the low-photon-rate regime, the dimer sources in both the Bose-Einstein condensate (BEC) and Bardeen-Cooper-Schrieffer (BCS) limits yield substantial capacity improvements over conventional sources. Specifically, at the operationally relevant PPM order of M = 128, the increase relative to lasers reaches up to ∼37% (BEC) and ∼94% (BCS), respectively. These results underscore photon-statistics and correlation engineering as a promising degree of freedom for maximizing photon information efficiency under stringent power and transceiver constraints.
PMID:42224570 | DOI:10.1364/OL.592295
