Nonlinear Photonic Quasicrystals for Novel Optical Devices
Two well-known methods for the design of quasicrystal models are used to create novel nonlinear optical devices. These devices are useful for efficient three-wave mixing of several different processes, and therefore offer greater flexibility with respect to the more common periodic nonlinear photonic crystals. We demonstrate applications for polarization switching as well as multi-wavelength and multi-directional frequency doubling. The generalized dual grid method is proven to be efficient for designing photonic quasicrystals for one-dimensional collinear devices as well as elaborate two-dimensional multi-directional devices. The cut and project method is physically realized by sending finite-width optical beams at an irrational angle through a periodic two-dimensional nonlinear photonic crystal. This enables two simultaneous collinear optical processes that can be varied by changing the angle of the beams.