EXCITED-STATE ABSORPTION AND STIMULATED EMISSION OF TETRAHEDRAL CO2+ ION IN LIGA5O8

Differential absorption spectra measurements of tetrahedral Co2+-doped LiGa5O8 have been made using a ps pump-probe technique. The stimulated emission from the 4T1(4P) level to the 4A2(4F) and 4T2(4F) states is observed to be overlapped by the excited-state absorption. The excited-state absorption is tentatively assigned to transition from the 4T1(4P) level of the Co2+ ion to the conduction band of LiGa5O8. For Co2+:LiGa5O8, laser operation is expected to be possible in the vicinity of 720 nm and in the 860–970 nm spectral region.