Comparative investigation of diode pumping for continuous-wave and mode-locked CR3+ : LiCAF lasers

Abstract

Cr3+ doped colquiriites are promising solid-state gain media for developing inexpensive and highly efficient tunable continuous-wave (cw) and femtosecond lasers. Among Cr3+ doped colquiriites,Cr3+:LiCAF has superior thermal properties enabling high-power operation with standard laser cavities. In this study we present detailed laser experiments with Cr3+:LiCAF, which achieve laser performance approaching that of the much more expensive Ti:sapphire laser technology. Inexpensive, new, multimode (similar to 1.5 W) and single-mode (similar to 150 mW) diode lasers were used as pump sources. With multimode diode pumping, cw output powers exceeding 1 W and mode-locked pulse energies as high as 2.8 nJ were obtained. Using single-mode diode pumping, up to 280 mW of cw output power with 54% slope efficiency and continuous tuning between 765 and 865 nm were demonstrated. In cw mode-locking, 72 fs, 1.4 nJ pulses were obtained, and an electrical-to-optical conversion efficiency of 7.8%, was demonstrated.