Femtosecond Laser Direct Writing of Compact Tm:YLF Waveguide Lasers

Waveguide lasers with compact packages have attracted great interest in recent years due to the rapid development of integrated photonics and the urgent demand for miniaturized photonic devices. In this work, we fabricate cladding waveguides in Tm:YLF crystal by femtosecond laser direct writing (FsLDW) technology. Pumped by Ti:sapphire laser at 779 nm, we achieve a low-threshold waveguide laser at 1877 nm. By further employing a Bi2Se3-based saturable absorber (SA) element, a pulsed Q-switched Tm:YLF waveguide laser is demonstrated. The experimental results achieved in this work show the great potential of Tm:YLF and FsLDW in the construction of mid-infrared lasers with compact designs.