Dynamically stable continuous single frequency green ring laser

A single-frequency ring laser using two standard commercial diode-pumped Nd:YAG modules is demonstrated. Employing a dynamically stable resonator design, multi-longitudinal mode operation at 1064 nm with 53 W of output power was obtained. When inserting a LBO crystal in the resonator, 1.8 W of single-sided, single-frequency output at 532 nm was achieved. The measured linewidth was 3.6 MHz, close to the resolution limit of the scanning etalon used to measure the longitudinal mode structure.