Photonic crystal cavity with self-similar structure and single-photon Kerr nonlinearities

Abstract

We propose a design of photonic crystal cavity with self-similar electromagnetic boundary conditions, that achieve ultrasmall mode volume (Vff). The electric energy density of a cavity mode can be maximized in the air or dielectric region, depending on the choice of boundary conditions. We illustrate the design concept with a silicon-air ID photon crystal cavity that reaches an ultrasmall mode volume of Vff ~ 7.01 x 10- 5 [lambda]3 at [lambda] ~ 1550 nm. We show that the extreme light concentration in our design can enable ultra-strong Kerr nonlinearities, even at the single photon level. These features open new directions in cavity quantum electrodynamics, spectroscopy, and quantum nonlinear optics.