MBI-Mitarbeiter - Persönliche Daten

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

  1. Ytterbium doped phosphate laser glasses

    S. Jiang, M.J. Myers, D.L. Rhonehouse, S.J. Hamlin, J.D. Myers, U. Griebner, R. Koch, H. Schönnagel

    SPIE Proceedings 2986 (1997) 10-15
  2. Fiberbündel-Laser hoher Durchschnittsleistung

    U. Griebner

    Dissertation Technische Universität (1997)
  3. Laser performance of a new ytterbium doped phosphate laser glass

    U. Griebner, R. Koch, H. Schönnagel, S. Jiang, M.J. Myers, D. Rhonehouse, S.J. Hamlin, W.A. Clarkson, D.C. Hanna

    OSA Trends in Optics and Photonics 1 (1996) 26-29
  4. Efficient laser operation with nearly diffraction-limited output from a diode-pumped heavily Nd-doped multimode-fiber

    U. Griebner, R. Koch, H. Schönnagel, R. Grunwald

    Opt. Lett. 21 (1996) 266-268
  5. Passively Q-switched Nd:glass fibre-bundle laser

    U. Griebner, R. Koch

    Electron. Lett. 31 (1995) 205-206
  6. High-average-power flashlamp-pumped Nd:Glass fiber-bundle laser

    R. Koch, U. Griebner, R. Grunwald

    Applied Physics B 58 (1994) 403-407
  7. Segmented solid-state laser resonators with graded reflectance micro-mirror analysis

    R. Grunwald, U. Griebner

    Pure Appl. Opt. 3 (1994) 435-440