26 Apr 2019
Titanium-doped sapphire (Ti3+:Al2O3) is a widely used transition-metal doped laser crystal. The Ti3+ ion has a very large gain bandwidth, that opens possibility to obtain very wide wavelength tunability realized in short pulse lasers. To obtain crystals with good optical quality Ti3+doping concentration should not exceed 0,25 at.%. Thus the crystals with thickness of several millimeters have to be used. The crystal is characterized by short upper-state lifetime and high saturation power. All these facts lead to necessity of strongly focused pump beam usage.