Member of project 3.2 "Solids and Nanostructures: Electrons, Spins, and Phonons"
The activity of our research group is centered around the direct laser writing of 3d micro-optical systems in solid transparent materials with fs-laser pulses. Our activity is divided in the two topics of (i) Fundamentals of the laser-matter interaction during microprocessing with ultrashort laser pulses and (ii) Direct laser printing of photonic structures with ultrafast laser pulses.
Topic (i) aims at:
- determining which fundamental mechanisms prevail during plasma formation with ultrashort pulses
- studying the relaxation processes leading to structural modifications, for instance thermal transients and defect formation.
Topic (ii) deals with the fabrication of functional micro-optical systems, mainly in the bulk of fused silica. The main applications include:
- Long term data storage
- Direct part marking under the surface
- Printing of integrated optical sensors
Since 2015: Principal Investigator on a DFG-funded research project entitled “Micromachining with few-cycle pulses”
2009-: Research associateat the Max-Born Institute, Berlin. Developed, designed and tested advanced optical methods for the characterization of femtosecond-laser induced micro- and nanostructures in the volume of transparent materials: phase-contrast microscopy, quantitative phase-shift interferometry, time-resolved microscopy with random lasers.
2008-2009: Project associateoptics/sensors,Hella Aglaia Mobile Vision GmbH, Berlin. Participated in the development of a front camera for car driver assistance, designed and tested an optical method able to measure the modulation transfer function of the cameras in a production environment.
2007-2008: Research associate,Princeton University, Princeton, NJ, USA. Developed and characterized a new generation of adaptive optics components based on tunable acoustic lenses. Demonstrated applications in imaging (microscopy, fast zoom lens) and non imaging optics (beam focusing, spatial beam shaping). Promoted devices to investors and users. Participated in device patenting. Technology commercially available (www.tag-optics.com).
- Flipping the sign of refractive index changes in ultrafast and temporally shaped laser-irradiated borosilicate crown optical glass at high repetition rates Physical Review B 77 (2008) 104205/1-8
- Spatial distribution of refractive index variations induced in bulk fused silica by single ultrashort and short laser pulses Journal of Applied Physics 101 (2007) 043506/1-7
- Analysis and optimization of ultrafast laser induced bulk modification in transparent materialsDissertation Freie Universität Berlin and Université Jean Monnet, Institut Superieur Des Techniques Avancees (2007)
- Transient response of dielectric materials exposed to ultrafast laser radiation Applied Physics A - Materials Science & Processing 84 (2006) 413-422
- Tailored excitation sequences for optimized laser-induced modifications in bulk transparent materials exposed to sub-ps irradiation Photonics Photon Processing in Microelectronics and Photonics V 6106 SPIE Proceedings (2006) 610601/1-9
- Direct observation of femtosecond laser induced modifications in the bulk of fused silica by phase contrast microscopy Journal of Laser Micro/Nanoengineering 1 (2006) 155-160
- Optimization of ultrafast laser generated low-energy ion beams from silicon targets Applied Physics Letters 87 (2005) 124105/1-3
- Temporal pulse manipulation and consequences for ultrafast laser processing of materials Optical Engineering 44 (2005) 051106/1-10
- Adaptive control of ion beams produced by ultrafast laser ablation of silicon Ultrafast Phenomena in Semiconductors and Nanostructure Materials IX 5725-50 (2005) 329-343
- Temporal pulse manipulation and adaptive optimization in ultrafast laser processing of materials SPIE Proceedings 5662 SPIE, WA, 2004 (2004) 593-602