EFFICIENT AND TUNABLE DIODE-PUMPED FEMTOSECOND YB-GLASS LASERS

Diode-pumped Yb:phosphate and Yb:silicate glass lasers have been passi vely mode locked for the first time to the authors' knowledge. Reliabl e self-starting mode locking without critical cavity alignment has bee n achieved with intracavity semiconductor saturable-absorber mirrors a nd soliton mode locking. pulses as short as 58 fs with the Yb:phosphat e laser and 61 fs with the Yb:silicate laser at average output powers of 65 and 53 mW, respectively. The pulse repetition rate was 112 MHz, Additionally, we demonstrated tunability of femtosecond pulses from 10 25 to 1065 nm for the Yb:phosphate and from 1030 to 1082 nm for the Yb :silicate glasses. The highest mode-locked output power was 405 mW, wi th 183-fs pulses from the phosphate glass. The diode pump power was 1. 68 W, corresponding to 24% optical-to-optical efficiency. The highest cw output power was 510 mW at the same incident pump power. (C) 1998 O ptical Society of America.