Abstract

LiNbO₃ is a well-known and widely used crystal for its good electro-optic, acousto-optic, and non-linear properties. The combination of such properties with the laser gain of rare-earth ions in the same medium permits the construction of many intersting systems including self-Q-switched, self-mode-locked, and self-freqency-doubled laser devices. Since LiNbO₃ benefits from well-established techniques to form low loss waveguides and complex integrated optical functions, the further combination of rare-earth doped LiNbO₃ properties in a single-mode waveguide configuration can yield to efficient and monolithic multifunction compact devices. To name a few, the integration of modulators can simply mode-lock or Q-switch the laser with respectively a high-frequency and peak-power capability for low-drive voltages. Using the acousto-optic or electro-optic effect it is also possible to fabricate tunable single-frequency lasers with a potentially narrow linewidth. Compact visible laser sources can be fabricated by intra-cavity second-harmonic-generation using for instance the recently developped quasi-phase-matching techniques. Finally, implementing the already demonstrated large range of integrated optical functions on doped LiNbO₃ substrate should eventually provide insertion loss compensated amplified optical circuits.

© 1993 Optical Society of America