Abstract

Unidirectional single-frequency sources are very desirable for many applications, including those that involve nonlinear frequency conversion.^1-3 Unlike monolithic structures, open-cavity devices offer the potential for intracavity doubling.^3,4 Of the open cavity devices, a semimonolithic structure offers the advantage of compact design and high-effieiency/high-power diode-laser pump coupling. However, semimonolithic devices have suffered historically from power instabilities believed to be related to residual spatial hole burning at the pump interface.⁵ Off-axis pumping is one solution, but it requires that the pump radius be a fraction of the mode radius, which is difficult for higher-power pump sources.

© 1995 Optical Society of America