We report what is to our knowledge the first directly diode-pumped tunable (over 120 nm) continuous-wave Cr<sup>4+</sup>: YAG laser, operating near 1.5 μm . At room temperature the laser delivered as much as 200 mW of power at 4 W of absorbed pump power. We also report observation of slow laser output degradation and bleaching in highly concentrated cyrstals, which we suggest is due to a photorefractive phenomenon.
© 1999 Optical Society of America
I. T. Sorokina, S. Naumov, E. Sorokin, E. Wintner, and A. V. Shestakov, "Directly diode-pumped tunable continuous-wave room-temperature Cr4+:YAG laser," Opt. Lett. 24, 1578-1580 (1999)