Progress on ultra-fast laser crystals

Femtosecond laser sources have become essential for a large range of applications, such as high-capacity telecommunication systems, ultrafast spectroscopy, micromachining, and optical coherence tomography. For the past decade, the interest on the Yb-doped materials for femtosecond diode-pumped laser applications is growing, which are established to be particularly suitable for directly diode-pumped, high-power, solid-state sources. A new Yb-doped oxyorthosilicate laser crystal, Yb:Gd₂SiO₅ (Yb:GSO), and mixed crystals such as Yb:(Lu_1-xY_x)₂SiO5 and Yb:(Gd_1-xY_x)₂SiO₅ have been grown. Laser experiment, a slope efficiency up to 86%. a low threshold of 77mW and 343fs mode-locked pulses were achieved for a continuous wave Yb:GSO laser around 1031, 1048,1088 and 1092.5nm respectively. 210-fs laser pulses were achieved at 1093-nm by a self-starting mode-locked Yb:GYSO laser.