Broadly tunable cw laser emission is reported in Tm:YAG and Tm:YSGG at room temperature with Ti:sapphire laser pumping. The Tm(3+)(3)F(4) ? (3)H(6) transition is tuned continuously over the ranges 1.87-2.16 microm in YAG and 1.85-2.14 microm in YSGG. Smooth tuning results from overlapping transitions between phonon-broadened crystal field Stark levels.

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Efficient cw operation of the Er(3+):GSGG (4)I(11/2)?(4)I(13/2) laser transition at 2.8 microm is demonstrated at room temperature. The (4)I(11/2) upper laser state is directly pumped at 0.97 microm. The slope efficiency for the 2.8-microm laser is 36%, indicating a greater than unity quantum efficiency. This excess efficiency results from the recycling of population through upconversion out of the lower laser state.

The 2.09-microm Ho:YAG (5)I(7) ? (5)I(8) laser transition is intracavity pumped by a Tm:YAG laser. Separate Tm:YAG and Ho:YAG crystals share a single laser cavity, the Tm:YAG crystal is pumped at 785 nm, and the resulting 2.01-microm Tm(3+) laser emission pumps the Ho:YAG crystal. The slope efficiency of the 2.09-microm Ho(3+) laser output is 42% of the absorbed 785-nm pump power.

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