Optical Parametric Oscillator in a Lithium Niobate Photonic Crystal Membrane

The unusual, controllable dispersion properties of photonic crystals (PhCs) led to several unique applications, such as waveguiding with engineered dispersion, high transmission at sharp waveguide bends, self-collimation, superprisms or low-bandwidth notch filters. Recent technological progress allowed for microstructuring lithium niobate (LiNbO₃), a nonlinear optical crystal with large second order nonlinearity. Microcavites in this nonlinear medium allow for different optical functionalities, such as second harmonic generation and optical parametric oscillation, recently investigated in a two-dimensional system with a cavity quality factor of Q = 5,000. In this presentation we shall investigate a microcavity optical parametric oscillator (OPO) in a realistic three-dimensional PhC, namely a PhC membrane. The device has a very small footprint and could be realized on an optical chip.