Bandwidth control of paired photons generated in monolithic Bragg reflection waveguides.

Bragg reflection waveguides are considered as monolithic sources of frequency correlated photon pairs generated using spontaneous-parametric down-conversion in a AlxGa1-xAs material system. The source described here offers unprecedented control over the process bandwidth, enabling bandwidth tunability between 1 nm and 450 nm while using the same wafer structure. This tuning is achieved by exploiting the powerful control over the waveguide dispersion properties afforded by the phase-matching technique used. The offered technology provides a route for realizing electrically pumped, monolithic photon pair sources on a chip with versatile characteristics.