Dr. Uwe Griebner
uwe.griebner(at)mbi-berlin.de
+49 30 6392 1457
C2: Solid State Light Sources
Haus 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 Publikationen
- Generation of femtosecond Bessel beams with micro-axicon arrays Optics Letters 25 (2000) 981-983
- High average power ultrafast fiber CPA system Applied Physics B 71 (2000) 889-891
- Cladding-pumped Yb:YAG planar waveguide laser; in: Advanced Solid State Lasers; H. Injeyan, U. Keller, C. Marshall (Eds.) OSA Trends in Optics and Photonics 34 (2000) 431-433
- Laser with guided pump and free-propagating resonator mode using diffusion-bonded rectangular channel waveguides Applied Physics Letters 77 (2000) 3505-3507
- Short-pulse KrF laser with M2 reduction by a super-Gaussian mirror SPIE Proceedings Series 3611 (1999) 102-111
- Generation of thin film microoptics by crossed deposition through wire-grid masks SPIE Proceedings Series 3825 (1999) 136-143
- Thermally bonded Yb:YAG planar waveguide laser Optics Communications 164 (1999) 185-190
- Laser operation with nearly diffraction limited output from a Yb:YAG multimode channel waveguide Opt. Lett. 24 (1999) 750-752
- Compact diode-pumped microlaser with mode-selective thin film micro-mirrors in: Advanced Solid State Lasers, M.M. Fejer, H. Injeyan, U. Keller (Eds.),OSA Trends in Optics and Photonics Series (TOPS) 26 (1999) 208-211
- Frequency doubling and autocorrelation studies of 20 fs pulses using polycrystalline zinc oxide thin films Applied Physics B 67 (1998) 757-760