Integrated twin-photon sources for the silicon absorption band: a numerical study

S. Ducci, G. Leo, V. Berger, A. De Rossi, and G. Assanto

J. Opt. Soc. Am. B 22, 2331-2337 (2005)

Abstract:

We numerically study a narrowband semiconductor integrated source of counterpropagating twin photons for line-of-sight experiments in quantum key distribution. Considering the air transparency and the availability of silicon avalanche photodiodes to be around 770 nm, we focus on GaN- and ZnSe-based quadratically nonlinear multilayer waveguides. The design of a quasi-phase-matched &chi^(2) profile in the growth direction allows us to generate 3×105 guided photon pairs per second for a pump power around 300 mW.