Growth, Spectroscopy and Laser Operation of Tm3+, Li+-Codoped Ca3Ta1.5Ga3.5O12-Type Disordered Garnet Crystal

Calcium niobium gallium garnet (CNGG) crystals doped with thulium (Tm 3+ ) ions possess disordered structure leading to inhomogeneously broadened emission bands which makes them attractive for generation of ultrashort pulses at ~2 μm [1] . The actual composition of CNGG deviates from the stoichiometry and cationic vacancies are present to ensure charge compensation. They can be eliminated by codoping with univalent alkali cations (Li + , Na + ). The related calcium tantalum gallium garnet (CTGG) shows better thermal properties than CNGG [2] . Here, we report on the growth, spectroscopy and first laser action in a Tm 3+ ,Li + -codoped CTGG (Tm:CLTGG) crystal.