MBI Staff Member – Personal info
Dr. Uwe Griebner
uwe.griebner(at)mbi-berlin.de
+49 30 6392 1457
C2: Solid State Light Sources
Building C, 2.22

Position
Project Coordinator 4.1: Implementation of Lasers and Measuring Techniques
Research
Development of advanced ultrashort pulse lasers, amplifiers, and parametric devices operating in the near- and mid-IR wavelength ranges including components and complete systems for direct implementation within other projects at MBI.
An example is the development of novel CPA laser sources emitting around 2 µm wavelength. This laser system operating at kilohertz repetition rate will serve as driver for OPCPA in the mid-IR. Figure (a) shows the simulated bifurcation diagram of a Ho:YLF regenerative amplifier (RA) at a 1 kHz repetition rate and 24 round trips indicating the most interesting operation regimes, i.e., stable double-pulsing (yellow coded bar) and the single-energy regime (green coded bar) beyond the final bifurcation point (BP final). Based on our model the RA is designed for operation in the single-energy regime beyond BPfinal. The measured complete RA bifurcation diagram of the re-designed RA at 1 kHz and 24 round trips is presented in Fig. (b). It agrees well with our numerical simulations [Fig. (a)]. Only the predicted multi-pulsing between 20 and 30 W pump power is less pronounced in the experiment. The highest pulse energy of 12 mJ can be extracted in the stable double-pulsing regime in the upper bifurcation branch (yellow coded bar), however at 0.5 kHz, the half of the repetition rate. BPfinal appears at a pump power of 47 W and denotes the transition to the single-energy regime where any multi-stabilities and chaotic behavior have been overcome. The extracted RA pulse energy of 9.7 mJ is the by far highest reported for 2-µm RAs operating in the single-energy regime. Taking into account the applied pump power of 50 W, the extraction efficiency is as high as 19.5%. Performing the transition from the stable double-pulsing to the single-energy regime, the RA’s pulse-to-pulse stability is further improved with a rms value <0.5%. Figure (c) shows the corresponding pulse stability measurement in the vicinity of BPfinal and beyond in the single-energy regime (green coded bar).
Curriculum vitae
since 1992 Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Berlin, Germany, staff scientist and project coordinator.
1993 - 1996 Ph.D. thesis at the Optical Institute, Technical University Berlin, Germany, with Prof. Horst Weber,
Title of thesis: Fiber bundle lasers with high average power,
1989 - 1992 Institute of Nonlinear Optics and Short Pulse Spectroscopy, Berlin, Germany, staff scientist,
1986 - 1989 Institute of Mechanics, Chemnitz, Germany, staff scientist,
1981 - 1986 Diploma degree in Physics; Physics Department, University of Jena, Germany,
Title of thesis: Characterization of lattice distorsions in LiF crystals,
MBI Publications
- Pulsed 2-micron lasers based on Tm3+-doped monoclinic double tungstate crystals SPIE Proceedings Series 8039 (2011) 803902/1-9
- Diode-pumped Ho:KLu(WO4)2 laser at 2.08 mm Applied Physics Express 4 (2011) 072601/1-3
- Continuous-wave and Q-switched Tm-doped KY(WO4)2 planar waveguide laser at 1.84 mm Optics Express 19 (2011) 1449-1454
- Continuous-wave co-lasing in a monoclinic co-doped (Ho,Tm):KLu(WO4)2 crystal Laser Physics Letters 8 (2011) 799-803
- Pulse repetition rate up to 92 GHz or pulse duration shorter than 110 fs from a mode-locked semiconductor disk laser Applied Physics Letters 98 (2011) 071103/1-3
- Diode-pumped mode-locked Yb:YCOB laser generating 35 fs pulses Optics Letters 36 (2011) 4425-4427
- Broad emission band of Yb3+ in the nonlinear Nb:RbTiOPO4 crystal: origin and applications Optics Express 18 (2010) 7228-7242
- Thin disk Tm-laser based on highly doped Tm:KLu(WO4)2/KLu(WO4)2 Laser Physics Letters 7 (2010) 435-439
- CW laser operation of a highly-doped Tm:KLu(WO4)2/KLu(WO4)2 thin disk epitaxial laser SPIE Proceedings Series 7578 (2010) 75780E/1-8
- Passive mode-locking of acentric Yb-doped borate crystals Laser Physics 20 (2010) 1085-1090