Continuous-wave broadly tunable orange-red generation with an intracavity frequency-doubled Cr4+: forsterite laser

Abstract

Continuous-wave orange-red light was generated from a room-temperature intracavity frequency-doubled Cr4+:forsterite laser pumped by a 1064-nm Nd:YAG laser. Intracavity doubling was achieved by using a 2-cm-long periodically poled lithium niobate (PPLN) crystal which had gratings with different poling periods. At the PPLN crystal temperature of 188 degreesC, broadly tunable orange-red radiation could be obtained between 613 and 655 nm. With an incident pump power of 6.8 W at 1064 nm, the Cr4+:forsterite laser produced 245 mW and 45 mW of continuous-wave output power at the fundamental (1260 nm) and second harmonic (630 nm) wavelengths, respectively.