Quasi-Phase Matched Stacks of InP for Frequency Conversion

Phase matching for frequency conversion can in principle be achieved with cubic crystals with high nonlinear optical coefficients, high damage thresholds and wide regions of optical transparency by using a periodic arrangement of thin plates of the material oriented such that the sign of the nonlinearity reverses from plate to plate. In practice, it has proved difficult to produce a large number of lamellae of correct thickness, orientation and optical quality for operational devices. We propose a novel bonding technique of individual lamellae for the fabrication of InP quasi-phase matched stacks. Potential features of the process include interfaces of low loss without altering the nonlinear optical properties of the bulk. The stacks will be characterized by transmission measurements and frequency conversion efficiency. The process will also be applicable to other nonlinear optical semiconductor crystals, e.g. GaAs, GaP, GaSb, ZnS, ZnSe, ZnTe and CdTe. Frequency conversion by QPM stacks of semiconductor crystals in the IR may be applied to spectroscopy, remote sensing and LIDAR, monitoring the Earth's atmosphere from satellites to acquire meteorological and environmental data.