Recent development of nonlinear optical borate crystals: key materials forgeneration of visible and UV light

The development of nonlinear optical (NLO) berate crystals for generation o f visible and UV light is reviewed. We first discussed on the basic princip les of laser frequency conversion. Then, we examine the trends in research on NLO crystals. The background and present status of NLO berate crystals a re summarized. The main considerations are focused on the discussion of cry stals like CsLiB6O10 (CLBO), GdxY1-xCa4O(BO3)(3) (GdYCOB) and K2Al2B2O7 (KA B). Properties of related materials like beta -BaB2O2 (BBO), LiB3O5 (LBO), KBe2BO3F2 (KBBF), Sr2Be2BO7 (SBBO), CsB3O5 (CBO), GdCa4O(BO3)(3) (GdCOB) an d YCa4O(BO3)(3) (YCOB) are included for comparison. We aim to provide a com plete view of developing a new NLO berate material for actual laser applica tions. This review covers various aspects including the search for new mate rials, the growth of bulk crystals, the characterization of crystal propert ies as well as the development of new techniques to overcome obstacles in a ctual laser application, namely, thermal dephasing and laser-induced damage . Finally, perspectives on NLO berate crystals and all-solid-state UV laser s are evaluated. (C) 2000 Elsevier Science B.V. All rights reserved.