Direct diode-pumped 58 fs Yb:Sr3Y2(BO3)4 laser

• Nonlinear refractive index of Yb:Sr3Y2(BO3)4 crystal was studied for the first time.
• Ultrafast laser performance of Yb:Sr3Y2(BO3)4 was demonstrated for the first time.
• The SESAM-assisted Kerr-lens mode-locked Yb:SYB laser generated 58 fs pulses with a maximum average output power of 400 mW.

The ultrafast laser performance of Yb:Sr3Y2(BO3)4 (SYB) crystal has been demonstrated for the first time to the best of our knowledge. The Yb:SYB laser was driven to work in SESAM-assisted Kerr-lens mode-locking (KLM) operation, and 58 fs pulses were generated at the central wavelength of 1054.6 nm. A maximum average output power reached 400 mW with a slope efficiency of 13.5%. The experimental results indicated Yb:SYB crystal as a promising candidate for achieving ultrashort lasers.