Nonlinear silicon photonics

Silicon is evolving as a versatile photonic platform with multiple functionalities that can be seamlessly integrated. The tool box is rich starting from the ability to guide and amplify multiple wavelength sources at GHz bandwidths, to optomechanical MEMS. The strong confinement of light in ultra small structures also enables the generation of strong optical forces. We have recently shown that nonlinear optical forces can enable controllable manipulation of photonic structures. These advances should enable future micro-optomechanical systems (MOMS) with novel and distinct functionalities. A research area that recently has emerged is nonlinear optics using silicon photonics. Since the birth of nonlinear optics, researchers have continually focused on developing efficient nonlinear optical devices that require low optical powers. The strong light confinement in silicon waveguides results in a high effective nonlinearity ad enables fine tuning of waveguide dispersion which is essential for phase matching of parametric nonlinear optical processes such as four-wave-mixing (FWM) We demonstrated FWM-based frequency conversion in waveguides using as little as 1 mW of pump power in a ring-resonator geometry, and ~100 mW of pump power over bandwidths exceeding 800 nm in a straight-waveguide device. In addition, by using the concept of time-space duality we have shown the temporally stretching and compressing of optical waveforms which allows for seamless transformation between the GHz and THz regimes.