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,
- Diamond saw dicing of thulium channel waveguide lasers in monoclinic crystalline films Optics Letters 44 (2019) 1596-1599
- Graphene and SESAM mode-locked Yb:CNGS lasers with self-frequency doubling properties Optics Express 27 (2019) 590-596
- 67-fs pulse generation from a mode-locked Tm,Ho:CLNGG laser at 2083 nm Optics Express 27 (2019) 1922-1928
- Comparative study of Yb:KYW planar waveguide lasers Q-switched by direct- and evanescent-field interaction with carbon nanotubes Optics Express 27 (2019) 1488-1496
- Passive Q-switching of femtosecond-laser-written Tm:KLu(WO4)2 waveguide lasers by graphene and MoS2 saturable absorbers SPIE Proceedings Series 10511 (2018) 105110A/1-6
- Tm:GdVO4 microchip laser Q-switched by a Sb2Te3 topological insulator SPIE Proceedings Series 10511 (2018) 105110B/1-7
- Dual-wavelength Nd:CaLnAlO4 lasers at 1.365 and 1.390 μm SPIE Proceedings Series 10511 (2018) 105111V/1-9
- Crystal growth, spectroscopy and first laser operation of a novel disordered tetragonal Tm:Na2La4(WO4)7 tungstate crystal Journal of Luminescence 203 (2018) 676-682
- Generation of 84-fs pulses from a mode-locked Tm:CNNGG disordered garnet crystal laser Photonics Research 6 (2018) 800-804
- Comparative study of the spectroscopic and laser properties of Tm3+, Na+(Li+)-codoped Ca3Nb1.5Ga3.5O12 -type disordered garnet crystals for mode-locked lasers Optical Materials Express 8 (2018) 2287-2299