MQ Photonics, Department of Physics, Macquarie University, Sydney, NSW 2109, Australia.
Molecules. 2020 Aug 27;25(17):3925. doi: 10.3390/molecules25173925.
Low-loss photonic waveguides in lithium niobate offer versatile functionality as nonlinear frequency converters, switches, and modulators for integrated optics. Combining the flexibility of laser processing with liquid phase epitaxy we have fabricated and characterized lithium niobate channel waveguides on lithium niobate and lithium tantalate. We used liquid phase epitaxy with KO flux on laser-machined lithium niobate and lithium tantalate substrates. The laser-driven rapid-prototyping technique can be programmed to give machined features of various sizes, and liquid phase epitaxy produces high quality single-crystal, lithium niobate channels. The surface roughness of the lithium niobate channels on a lithium tantalate substrate was measured to be 90 nm. The lithium niobate channel waveguides exhibit propagation losses of 0.26 ± 0.04 dB/mm at a wavelength of 633 nm. Second harmonic generation at 980 nm was demonstrated using the channel waveguides, indicating that these waveguides retain their nonlinear optical properties.
在铌酸锂中，低损耗光子波导作为非线性频率转换器、开关和调制器，为集成光学提供了多功能性。我们将激光加工的灵活性与液相外延相结合，在铌酸锂和钽酸锂上制造和表征了铌酸锂通道波导。我们在激光加工的铌酸锂和钽酸锂衬底上使用了 K0 通量的液相外延。激光驱动的快速原型制作技术可以编程，以获得各种尺寸的加工特征，并且液相外延产生高质量的单晶铌酸锂通道。在钽酸锂衬底上的铌酸锂通道的表面粗糙度测量为 90nm。在 633nm 波长下，铌酸锂通道波导的传播损耗为 0.26±0.04dB/mm。使用通道波导演示了 980nm 的二次谐波产生，表明这些波导保留了它们的非线性光学性质。
