High efficiency UV solid state lasers based on Ce:LiCaAlF6 crystals

We report the spectroscopy and laser results of cerium-doped colquiriite LiCaAlF6 (LiCAF) single crystals. High quality samples have been grown using the Czochralski technique and characterized by means of X-ray Laue diffractometry, absorption and emission spectra. Moreover, we measured the lifetime and deduced the emission cross-sections of the laser transition. Using this crystal we realized two lasers devices: a high-efficiency laser emitting at 289 nm with a repetition rate (RR) of up to 2 kHz and a widely tunable laser (from 280 nm to 317 nm) with an RR of up to 4.3 kHz. The high quality of the crystal made it possible to obtain the highest slope efficiency (49%) ever reported to our knowledge for a Ce:LiCAF laser.