Excited-state absorption and stimulated emission in Cr4+-doped oxide crystals

摘要

Excited state absorption spectra of Cr$+4$PLU$/-doped garnets and wurtzite-like crystals were measured between 400 nm and 2000 nm. In Cr$+4$PLU$/:Y$-3$/Al$-5$/O$-12$/, a strong polarization dependence of the excited state absorption is observed, while it diminishes for Cr$+4$PLU$/:Y$-3$/Sc$-0.5$/Al$-4.5$/O$-12$/ and is almost not observed in Cr$+4$PLU$/:Y$-3$/Sc$-2$/Ga$-3$/O$-12$/. FOr Cr$+4$PLU$/:LiAlO$-2$/ and Cr$+4$PLU$/:LiGaO$-2$/ the region of the emission is overlapped by excited state absorption and nonlaser oscillation at room temperature is expected.