Abstract

A diode pumped unidirectional single longitudinal mode Nd:YAG ring laser is described which was operated on both the fundamental and second harmonic wavelengths. The slope efficiency, second harmonic conversion efficiency, and electrical to optical efficiency are reported. The ring resonator consists of four elements; a 25-cm 98%R output couple, 2 HR flat mirrors, and a 6.4-mm diam by 5-mm long rod of 1.1% Nd:YAG. The rod is mounted in a high field magnet to obtain Faraday rotation. One of the two flat mirrors is mounted on a piezoelectric drive to allow tuning of the output frequency. The path taken in the resonator is in a diagonal configuration. The angle of incidence of all four elements is 9°, leading to a tangential and sagittal waist of 50 and 115 μm, respectively. Single longitudinal mode output power of 542 mW was obtained at 1.06 μm with a pump power of 1.59 W and a slope efficiency of 37%. An AR coated crystal of KTP was mounted intracavity to obtain over 14 mW of single frequency 532-nm output with a conversion efficiency of 2.5%.

© 1989 Optical Society of America