Efficient second harmonic generation green light in RTP planar waveguides

Abstract

In this paper, epitaxial layers of Rb1‐xBaxTi1‐y‐zYbyNbzOPO4 have been successfully grown on (001) oriented RbTiOPO4 substrates. Although the Ba2+ contents in these layers was very low, the contrasts in refractive indices between the epitaxial layer and the substrate were high enough to allow the propagation of one TE and three TM modes, at the wavelength of 632.8 nm, using a 5 μm thickness epilayer. These light propagation modes were first simulated, using the refractive indices of the layer and the substrate measured previously. The TE and TM dark‐mode spectra obtained experimentally, using the prism coupler method and a He‐Ne laser beam, agree well with the simulation results. Finally, type II Second Harmonic Generation experiments were carried out with pumping at 1130 nm and obtaining green light at 565 nm. The experimental efficiency in the Second Harmonic Generation experiments was of 69%/mWcm2. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)