Sub-50 fs pulse generation from a SESAM mode-locked Tm,Ho-codoped calcium aluminate laser

We report on sub-50 fs pulse generation from a passively mode-locked (ML) Tm,Ho-codoped crystalline laser operating in a 2 mu m spectral region. A Tm, Ho:Ca(Gd, Lu)AlO4 laser delivers pulses as short as 46 fs at 2033 nm with an average power of 121 mW at a pulse repetition rate of similar to 78 MHz employing a semiconductor saturable absorber mirror as a saturable absorber. To the best of our knowledge, this result represents the shortest pulses ever generated from a Tm- and/or Ho-based solid-state laser. Polarization switching in the anisotropic gain material is observed in the ML regime without any polarization selection elements which is essential for the shortest pulses. (C) 2021 Optical Society of America

Automated summary

We report on the generation of sub-50 fs pulses from a passively mode-locked Tm, Ho-codoped crystalline laser operating in the 2 mu m spectral region. This represents the shortest pulses ever generated from a Tm- and/or Ho-based solid-state laser. The use of a semiconductor saturable absorber mirror as a saturable absorber enables the laser to deliver pulses as short as 46 fs at 2033 nm with an average power of 121 mW at a pulse repetition rate of approximately 78 MHz.