Abstract

Ultrashort-pulse lasers operating around 2 μm spectral region are of great interest for applications in time resolved spectroscopy, nonlinear frequency upconversion, optical communications and photomedicine. Tm³⁺ doped and Tm³⁺,Ho³⁺ co-doped crystalline gain media represent an attractive option for creating of diode-pumped, efficient and broadly tunable lasers around 2 μm which can be further employed for ultrashort pulse generation through the modelocking techniques. In the past, the generation of sub-100 ps pulses was reported from Tm:YAG [1] and Tm,Ho:BaY₂F₈ [2] lasers using an active mode-locking technique. However, no passively mode-locked Tm-doped and Tm,Ho co-doped bulk lasers have been reported to date. Here we demonstrate, for the first time to our knowledge, a Tm³⁺,Ho³⁺:KY(WO₄)₂ (Tm,Ho:KYW) laser passively mode-locked by using semiconductor saturable absorber mirror (SESAM).

© 2009 IEEE