title: Femtosecond Cr:LiSAF and Cr:LiCAF lasers pumped by tapered diode lasers.
abstract: We report compact, low-cost and efficient Cr:Colquiriite lasers that are pumped by high brightness tapered laser diodes. The tapered laser diodes provided 1 to 1.2 W of output power around 675 nm, at an electrical-to-optical conversion efficiency of about 30%. Using a single tapered diode laser as the pump source, we have demonstrated output powers of 500 mW and 410 mW together with slope efficiencies of 47% and 41% from continuous wave (cw) Cr:LiSAF and Cr:LiCAF lasers, respectively. In cw mode-locked operation, sub-100-fs pulse trains with average power between 200 mW and 250 mW were obtained at repetition rates around 100 MHz. Upon pumping the Cr:Colquiriite lasers with two tapered laser diodes (one from each side of the crystal), we have observed scaling of cw powers to 850 mW in Cr:LiSAF and to 650 mW in Cr:LiCAF. From the double side pumped Cr:LiCAF laser, we have also obtained ~220 fs long pulses with 5.4 nJ of pulse energy at 77 MHz repetition rate. These are the highest energy levels reported from Cr:Colquiriite so far at these repetition rates. Our findings indicate that tapered diodes in the red spectral region are likely to become the standard pump source for Cr:Colquiriite lasers in the near future. Moreover, the simplified pumping scheme might facilitate efficient commercialization of Cr:Colquiriite systems, bearing the potential to significantly boost applications of cw and femtosecond lasers in this spectral region (750-1000 nm).
authors: Department of Physics and Center for Applied Photonics, University of Konstanz, D-78464 Konstanz, Germany. umit79@alum.mit.edu
authors: Umit
authors: U
authors: Demirbas
authors: Michael
authors: M
authors: Schmalz
authors: Bernd
authors: B
authors: Sumpf
authors: Götz
authors: G
authors: Erbert
authors: Gale S
authors: GS
authors: Petrich
authors: Leslie A
authors: LA
authors: Kolodziejski
authors: James G
authors: JG
authors: Fujimoto
authors: Franz X
authors: FX
authors: Kärtner
authors: Alfred
authors: A
authors: Leitenstorfer