Selective enhancement of nonlinear processes in linearly uncoupled silicon resonators

We experimentally demonstrate the feasibility of the use of integrated linearly uncoupled resonators, which are coupled solely through the nonlinear interaction, to selectively enhance or suppress nonlinear processes. This is exploited to selectively enhance dual-pump spontaneous four-wave mixing while suppressing the parasitic noise associated with single pump spontaneous four-wave mixing processes. A signal-to-noise ratio characterizing the generation of identical photon pairs of more than four orders of magnitude is reported, opening the way to a new class of integrated devices exploiting the unique properties of identical photon pairs in the same optical mode.