Improved optical quality of AgGaS2

Abstract

Single crystals of AgGaS₂ for nonlinear optical applications were grown by the Bridgman−Stockbarger technique. It was possible to prepare 0.5−cm cubes free of lamellar twins from the central region of the boules. Room−temperature absorption of as−grown crystals was below 0.3 cm⁻¹ through the whole transmission range. After an annealing process with additional sulfur, absorption was reduced to α−1 in the wavelength range λ=0.9−8.5 μm.