Direct Kerr-lens mode-locked Tm: LuYO3 ceramics laser

A direct Kerr-lens mode-locked Tm: LuYO3 ceramics laser without the aid of any mode-locked starting element is reported for the first time. The pulse duration as short as 259 fs and maximum average output power of 326 mW are obtained at a repetition rate of 97.1 MHz. The corresponding optical spectrum centered at 2053 nm exhibits a bandwidth of 19.8 nm, which indicates the presence of nearly Fourier transform-limited pulses. Such a Kerr-lens mode-locked Tm: LuYO3 ceramics laser is a promising ultrashort pulse source, with both the excellent laser characteristics of Tm: LuYO3 and the high-power 790 nm LD pumping scheme.