Potassium titanyl phosphate and its isomorphs: Growth, properties, and applications

Potassium titanyl phosphate (KTP) and its isomorphs have received enormous attention in the last 2 decades. In particular, KTP assumes importance due to its large nonlinear optic and electrooptic coefficients together with th e broad thermal and angular acceptance for second harmonic generation. This article provides an overview of the material aspects, structural, physical , and chemical properties and device feasibility of the KTP family of cryst als. Some of the current areas of research and development along with their significance in understanding the physical properties as well as device ap plications are addressed. Optical waveguide fabrication processes and chara cteristics with their relevance to the present-day technology are highlight ed. Studies performed so far have enabled us to understand the fundamental aspects of these materials and what needs to be pursued vigorously is the e xploitation of their device applications to the maximum extent.