High-power diode-pumped Tm:YLF slab laser

The aim is to develop a high-power Tm:YLF slab laser which can be utilized to pump a Ho slab laser. This paper present a Tm:YLF slab laser pumped by two diode-bar stacks from both ends, leading to a maximum output power of 192.5 W. The slab was sandwiched between two water-cooled copper heat sinks using 0.2-mm-thick indium foil. The Tm laser was enclosed in a sealed box flushed with dry air. The laser beam was sigma-polarized (polarization parallel to the a-axis of the YLF crystal). The dependence of the output power of the Tm:YLF laser on the temperature of the crystal-holder at incident pump power levels of 82 W, 450 W and 550 W has been measured.