| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1493777 | Optical Materials | 2015 | 6 Pages |
•A 2.9 μm laser crystal Tm,Ho:GdYTaO4 (Tm,Ho:GYTO) is grown by the Czochralski method.•The crystal has high crystalline quality.•Chemical etching is employed to investigate the defect structure with KOH etchant.•The spectra, level lifetimes are measured, and absorption transitions are assigned.•The Tm-Ho energy transfer mechanism in GYTO is also demonstrated.
A new promising 2.9 μm Tm,Ho:GdYTaO4 (Tm,Ho:GYTO) laser crystal was grown by the Czochralski method. The full width at half maximum (FWHM) of X-ray rocking curve on the (0 1 0) face is only 0.05°, which indicates that the crystal has high crystalline quality. The structure parameters of Tm,Ho:GYTO crystal were determined by Rietveld refinement method. Chemical etching is employed to investigate the defect structure of Tm,Ho:GYTO crystal with KOH etchant. The absorption, emission spectra, and level lifetimes were measured, and the corresponding absorption transitions were assigned. The absorption cross-section at 790 nm was calculated to be 2.04 × 10−20 cm2 and maximum emission-cross section at 2932 nm was 2.05 × 10−20 cm2. The level lifetimes of 5I6 and 5I7 are 131 μs and 4.09 ms, respectively. Compared with other hosts, such as Ho:YAG, the shorter lifetime of 5I7 and long lifetime of 5I6 in the Tm,Ho:GYTO crystal are easier to realize population inversion. The Tm–Ho energy transfer mechanism in GYTO is also demonstrated.
