Waveguide lasers and nonlinear devices in lithium niobate

During the last years a whole family of waveguide lasers has been developed in Er-diffusion doped LiNbO/sub 3/ substrates with conventional Ti-diffused channel guides. More recently, various types of very efficient, quasiphase-matched nonlinear frequency converters have been demonstrated in PPLN (periodically poled lithium niobate) also with Ti-diffused channel guides. Moreover, periodic poling of Ti,Er:LiNbO/sub 3/ waveguides was achieved. Using this technology the development of several attractive laser/nonlinear frequency converter combinations-integrated on the same substrate or even in the same waveguide structure-becomes possible. It is the aim of this contribution to briefly review the state of the art of Er-doped waveguide lasers and of quasi phase-matched nonlinear devices. Moreover, concepts of laser/frequency converter combinations are discussed and latest results are reported.