Cr3+/Tm3+ co-doped fluorogermanate glasses were prepared by melt-quenching technique, and their luminescent properties were investigated under excitation of Xenon lamp and 808 nm laser diode, respectively. Through strong sensitization of Cr3+, an enhanced 1.8 µm emission band of Tm3+: 3F4→3H6 can be achieved in an extremely extended excitation band of 380-900 nm. The possible energy transfer mechanism between Cr3+ and Tm3+ is rationally discussed. On the basis of experimental data, the highest energy transfer efficiency is up to 91.70%. Our results suggest this efficient Cr3+/Tm3+ co-doping system provides a selective pump mechanism for obtaining 1.8 µm laser and thus shows attractive applications in near-infrared fiber lasers and amplifiers.

A compact α-BaTeMo 2 O 9 Raman laser emitting at 1164.4 nm was realized driven by a diode-side-pumped Nd:YLF laser. With a laser diode pump power of 150 W and pulse repetition rate of 2.5 kHz, a maximum first-order Stokes average output power of 2.7 W was obtained. The corresponding pulse width, single pulse energy, and peak power were 16 ns, 1.08 mJ and 67.5 kW, respectively. The obtained high pulse energy benefited from the good storage capability of the Nd:YLF crystal.