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
- Structured laser beams: toward 2-µm femtosecond laser vortices Photonics Research 9 (2021) 357-363
- Comparative study of Yb:Lu3Al5O12 and Yb:Lu2O3 laser ceramics produced from laser-ablated nanopowders Ceramics International 47 (2021) 6633-6642
- Monoclinic zinc monotungstate Yb3+,Li+:ZnWO4: Part II. Polarized spectroscopy and laser operation Journal of Luminescence 231 (2021) 117811/1-12
- Growth, spectroscopy and laser operation of monoclinic Nd:CsGd(MoO4)2 crystal with a layered structure Journal of Luminescence 231 (2021) 117793/1-10
- Tm3+ and Ho3+ colasing in in-band pumped waveguides fabricated by femtosecond laser writing Optics Letters 46 (2021) 122-125
- Compact high-flux hard X-ray source driven by femtosecond mid-infrared pulses at a 1 kHz repetition rate Optics Letters 46 (2021) 210-213
- Spectroscopy and laser operation of highly-doped 10 at.% Yb:(Lu,Sc)2O3 ceramics Optical Materials 117 (2021) 111128/1-7
- Kerr-lens mode-locked Tm-doped sesquioxide ceramic laser Optics Letters 46 (2021) 3428-3431
- Spectroscopy and efficient laser operation around 2.8 μm of Er:(Lu,Sc)2O3 sesquioxide ceramics Journal of Luminescence 240 (2021) 118373/1-11
- Femtosecond multi-10-mJ pulses at 2 µm wavelength by compression in a hollow-core fiber Optics Letters 42 (2021) 3033-3036