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,
- Generation of few-cycle millijoule pulses at 5 μm employing a ZnGeP2-based OPCPA pumped with GW peak power pulses at 2 μm SPIE Proceedings Series 10713 (2018) 107130W/1-4
- 1.34 μm VECSEL mode-locked with a GaSb-based SESAM Optics Letters 43 (2018) 3353-3356
- Tm:KY1-x-yGdxLuy(WO4)2 planar waveguide laser passively Q-switched by single-walled carbon nanotubes Optics Express 26 (2018) 4961-4966
- Sb2Te3 thin film for the passive Q-switching of a Tm:GdVO4 laser Optical Materials Express 8 (2018) 1723-1732
- Ho:KY(WO4)2 thin-disk laser passively Q-switched by a GaSb-based SESAM Optics Express 26 (2018) 9011-9016
- Thermo-optic effects in Ho:KY(WO4)2 thin-disk lasers Optical Materials Express 8 (2018) 684-690
- Inkjet-printing of graphene saturable absorbers for ~2 µm bulk and waveguide lasers Optical Materials Express 8 (2018) 2803-2814
- Synthesis, spectroscopic characterization and laser operation of Ho3+ in “mixed” (Lu,Sc)2O3 ceramics Journal of Luminescence 203 (2018) 145-151
- Crystal growth, low-temperature spectroscopy and multi-watt laser operation of Yb:Ca3NbGa3Si2O14 Journal of Luminescence 197 (2018) 90-97
- Monoclinic Tm:MgWO4 crystal: Crystal-field analysis, tunable and vibronic laser demonstration Journal of Alloys and Compounds 763 (2018) 581-591