Saturday, April 8, 2017

NSTC/CREOL Distinguished Seminar: "Infrared near-field microscopy and spectroscopy“ by Dr. Fritz Keilmann, 4.10.17/3:30PM-4:30PM/CREOL RM 103

NSTC/CREOL Distinguished Seminar: "Infrared near-field microscopy and spectroscopy“ by Dr. Fritz Keilmann
Monday, April 10, 2017 3:30 PM to 4:30 PM
CREOL Room 103

Dr. Fritz Keilmann Ludwig-Maximilians-Universität

Near-field optical microscopy (by scattering from an AFM tip, s-SNOM) returns local absorbance from a tiny volume of only (20 nm)^3 under the tip apex, thus enabling VIS-to-IR-to-THz mapping at exciting 20-nm resolution. The mid-infrared is ideal for nanoscale chemical recognition by vibrational and phonon contrasts (FTIR). Near-field techniques now offer nano-FTIR, i.e. FTIR at nanometric spatial resolution. For this, broadband coherent MIR sources are essential and higly desirable, especially when combined with dual-comb operation. Application highlights will be presented of finding and characterizing natural nanoscale inhomogeneities, chemical as well as structural, in organic solar-conversion films, in bone/shell biomineral matter, and in slices through a cometary dust particle. Nano-FTIR is no less than the continued success story of FTIR-based chemical analysis into resolutions hundreds, if not thousands of times better than previously attainable. It is a highly welcome solution to nanoanalysis requirements in all nanotechnologies and nanosciences.

Fritz Keilmann studied meteorology and physics in München and received a Dr. rer. nat. for research on infrared plasma diagnostics. As postdoc of Ali Javan at MIT he developed antenna-based harmonic mixing and high-power THz lasers.  He has been at the Max-Planck Society from 1973 to 2012: Initally at the MPI für Festkörperforschung Stuttgart, he pioneered far-infrared nonlinear optics and spectroscopy of solids, and investigated phonon physics, microwave biological effects, carrier dynamics of semiconductors, far-infrared ellipsometry of superconductors, and cyclotron-pumping microscopy of quantum-Hall edge states. In 1995 he relocated to the MPI für Biochemie Martinsried where he pioneered infrared scattering near-field microscopy, and also dual-frequency comb Fourier-transform infrared spectroscopy.   From 2007 - 2012 he was with the MPI für Quantenoptik Garching, in the DFG Cluster "Munich-Centre for Advanced Photonics", developing broad-band infrared spectroscopic near-field microscopy.  He has been awarded the Kenneth J. Button prize 2009.  Besides operating his firm LASNIX, he is presently a Scientific Advisor to Neaspec GmbH, producer of near-field infrared microscopes, and continues his research at Ludwig-Maximilians-Universität, München, investigating soft matter and biological nanocomposites.

For additional information:
Konstantin Vodopyanov

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