Optical Properties of LiIO3 in the Far Infrared

Abstract
The absorption coefficient of LiIO3 has been measured at 300°, 80°, and 7°K for the ordinary and extra‐ordinary ray. The corresponding indices of refraction at 300°, 80°, and 17°K were also determined. Upon cooling from 300° to 7°K, the absorption coefficients decrease drastically in the 10–150‐cm−1 spectral region. At 7°K the absorption coefficient is less than 1 cm−1 for frequencies up to 80 and 90 cm−1 for Ec and E ⊥ c, respectively. This characteristic is important for far‐infrared generation by mixing of two laser frequencies.