Project Coordinator 4.1: Implementation of Lasers and Measuring Techniques
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).
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,
- Disordered Tm3+,Ho3+-codoped CNGG garnet crystal: Towards efficient laser materials for ultrashort pulse generation at ~2 μm Journal of Alloys and Compounds 853 (2021) 157100/1-14
- 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
- Tm3+ and Ho3+ colasing in codoped ultrafast laser inscribed in-band pumped waveguide laser Optics Letters 46 (2021) 122-125
- Ultrafast laser inscribed waveguide lasers in Tm:CALGO with depressed-index cladding Optics Express 28 (2020) 3528-3540
- Low-loss fs-laser-written surface waveguide lasers at >2 µm in monoclinic Tm3+:MgWO4 Optics Letters 45 (2020) 4060-4063
- Ultrafast laser inscription and ∼2μm laser operation of Y-branch splitters in monoclinic crystals Journal of Lightwave Technology 38 (2020) 4374-4384
- Watt-level ultrafast laser inscribed thulium waveguide lasers Progress in Quantum Electronics 72 (2020) 100266/1-20
- Multi-millijoule, few-cycle 5 μm OPCPA at 1 kHz repetition rate Optics Letters 45 (2020) 5998-6001
- 35 W continuous-wave Ho:YAG single-crystal fiber laser High Power Laser Science and Engineering 8 (2020) e25/1-5
- Spectroscopy and diode-pumped laser operation of transparent Tm:Lu3Al5O12 ceramics produced by solid-state sintering Optics Express 28 (2020) 28399-28413