Continuous-wave and modelocked Yb:YCOB thin disk laser: first demonstration and future prospects

Area of Science:

• Laser Physics and Photonics
• Materials Science for Optics

Background:

• Yb:YCOB possesses a broad emission bandwidth, making it suitable for femtosecond pulse generation.
• The thin disk laser geometry offers advantages for high-power laser operation.

Purpose of the Study:

• To investigate power scaling of Yb:YCOB in the thin disk geometry.
• To explore the feasibility of femtosecond pulse generation using Yb:YCOB in this configuration.
• To identify limitations for high-power mode-locked operation.

Main Methods:

• Demonstration of continuous-wave (CW) power scaling in a thin disk Yb:YCOB laser.
• Initial investigations into mode-locking performance of Yb:YCOB thin disks.
• Analysis of thermal aberrations in Yb:YCOB thin disks of varying thickness.

Main Results:

• Continuous-wave power scaling achieved up to 100 W with 40% optical-to-optical efficiency in multi-mode operation.
• Initial mode-locking demonstrated, producing pulses as short as 270 fs.
• Mode-locked average power was limited to <5 W due to transverse mode degradation caused by thermal aberrations in 300-400 µm thick disks.

Conclusions:

• Yb:YCOB is a viable material for femtosecond pulse generation in the thin disk geometry.
• Anisotropic thermal aberrations in thicker Yb:YCOB disks limit high-power mode-locked operation.
• Significantly thinner disks are necessary to overcome thermal limitations and enable high-power femtosecond pulse generation.