Diode-pumped Nd:YAG and Nd:glass spinning-disk lasers

Abstract

Results are presented showing that high laser output efficiencies and a significant reduction in thermal effects can be achieved by a spinning of an optically pumped disk of gain material in a laser cavity. Waste heat is removed from the disk by conduction to cold plates across a thin gas layer. With this approach, a diode-pumped Nd:YAG laser has been demonstrated at 10.3-W cw output power, TEM_00 mode, with a slope efficiency of 59%. A Nd:glass spinning-disk laser has also been demonstrated at 35-W cw, multimode, with a slope efficiency of 40%. As the disk revolution rate was scanned from 1 to 26 Hz, the laser power first increased to a maximum value then decreased for increasingly higher rates. However, when the laser resonator axis was advanced with respect to the pump, the optimum spin rate shifted to higher values.