Fabrication of low-loss Rb-exchanged ridge waveguides in z-cut KTiOPO4

We report on the fabrication and characterization of ridge waveguides in z-cut KTiOPO4 fabricated by Rb-ion exchange and subsequent precise diamond-blade dicing. Low attenuation values of 1.3 dB/cm (1.6 dB/cm) were determined at a wavelength of 1550 nm for TE (TM) polarization. Surface quality obtained by dicing is excellent for side walls of diced ridges and prepared end faces used for light coupling. The dispersion characteristics of the waveguides are determined and the results are compared to simulations. Finally, the nonlinear performance of the ridges is demonstrated by second harmonic generation of similar to 1060 nm pump light. (C) 2017 Optical Society of America under the terms of the OSA Open Access Publishing Agreement