Experimental investigation of a pulsed Rb-Ar excimer-pumped alkali laser

We present experimental results of an exciplex-pumped alkali laser (XPAL) at 780nm based on the 5(2)P(3/2) -> 5(2)S(1/2) transition of the Rb atom in mixtures of Rb vapor and Ar. A laboratory-built Ti: sapphire laser with a pulse repetition rate of 3 kHz and a pulse width of 100 ns is used as the pump source. The maximum laser pulse energy of 0.26 mu J at 780nm is obtained under an absorbed pump pulse energy of 42 mu J at 755nm in mixtures of Rb vapor and Ar at a temperature of 423 K, corresponding to an optical conversion efficiency of 0.62%. Further experiments show that the output laser at 780nm can always be detected for pump wavelengths ranging from 754 to 759 nm, indicating that Rb-Ar mixtures can be effectively pumped by commercial laser diodes ( LDs) with a bandwidth of 5 nm. (C) 2017 The Japan Society of Applied Physics