High‐power mode‐locked operation of Yb‐doped NaY(WO4)2 end‐pumped by laser diodes

Passively cw mode-locked laser operation of Yb-doped NaY(WO4)2 (Yb:NaYW) crystal was demonstrated with an average power of 400 mW. This is the highest power achieved from the mode-locked Yb:NaYW laser to our knowledge. The laser was end-pumped by a high power fiber pigtailed laser diode bar and the mode-locking was enabled by a semiconductor saturable absorber mirror (SESAM). The laser pulse duration was 1.1 ps, centered at the wavelength of 1019.7 nm with a bandwidth of 1.6 nm, and nearly transform-limited.