Experimental exploration of room-temperature Er:YAG cascade laser

Abstract

Room-temperature cascaded mid-infrared (MIR) pulsed laser output in Er:YAG crystal is reported. The 1469nm characteristic wavelength of the cascade emission is observed. The characteristic wavelength of the excited-state absorption (ESA) is determined as 1676nm. An Er:YAG crystal with concentration of 10at.% is adopted to compare the laser output energy in the cascaded and non-cascaded configuration. The maximum single pulse energy of MIR laser increases from 1.04mJ (non-cascade) to 1.51mJ (cascade), corresponding to a ratio of 45.2%. The “cyclic cascade” is considered to be the mechanism responsible for the laser performance optimization. The experimental results confirm the existance of cascade at room temperature in Er:YAG crystal. Moreover, cascade is helpful to improve the single pulse energy of MIR laser.