Abstract

The blue-green laser has been the scientist's Holy Grail for many years. However, rapid progress in new compound semiconductors, such as ZnMgSSe (Ref. 1) and GaN (Ref. 2). is making applications in a wide range of optical systems possible. SHG-related frequency doublers are expected to supplant gas lasers, e.g., Ar lasers, because of their high reliability and high output power. Their merits have been extended by a new organic SHG crystal of 8-(4'-acetylphenyl)-1,4-dioxa-8-azaspiro-[4.5] decane (APDA), developed by the Bridgman method.^3-5 This crystal has shown excellent transparency upto wavelengths around 380 nm and so is applicable to blue lasers. Concerning its nonlinear coefficient, d₃₃ = 50 pm/V, d₃₁ = 7 pm/V, and d_eff = 14.9 pm/V were obtained on the basis of maker-fringe measurements and phase-matched SHG experiments. Phase-matched SHG was demonstrated from a Ti-sapphire laser pumping in the wavelength range of 780 to 900 nm.

© 1995 Optical Society of America