Efficient broadband-spectrum oscillation of ultrashort-pulse Kerr-lens mode-locked Yb:YAG laser with intracavity nonlinear media overcoming the fluorescence spectrum limit

Efficient broadband spectrum oscillation was obtained directly from a laser-diode-pumped Kerr-lens mode-locked Yb:YAG laser with intracavity nonlinear media. The spectrum was expanded to around 1040 nm to 1070 nm. The spectrum is much broader than the fluorescence spectrum at 1050 nm.