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DFG-Project „Bayesian compressed sensing for nanoscale chemical mapping in the mid-infrared regime“ has started

17.02.2020

The DFG – project "Bayesian compressed sensing for nanoscale chemical mapping in the mid-infrared regime" has started at the beginning of this year. The project aims at the reduction of large amounts of data and measurement times in scanning probe-based spectroscopy with broadband infrared synchrotron radiation. Scanning probe techniques with their pixel-by-pixel data acquisition and conventional Fourier-transform schemes lead to prohibitive imaging times and enhanced radiation damage.

Within the frame of this project a novel hyperspectral imaging scheme based on Bayesian compressed sensing (BCS) shall be developed. The project will advance both, the mathematical concept of BCS as well as the scanning probe microscope (SPM) required for the implementation, with variable sample and interferometer positioning, and thus overcome the conventional pixel-by-pixel SPM paradigm. Our previous work already showed by means of a simplified approach an example for the successful reconstruction of spectral properties of the sample surface in the nanometer range using only 1/10th of all measurement points [1].

The proposed scheme will not only make hyperspectral imaging viable at the nanoscale. It also promises major advancement for the discrimination capability and detection sensitivity in nanoscale chemical mapping in general. The resulting rapid chemical nano-imaging technique promises widespread use in academic and industrial settings for fundamental and applied nano- and biomaterials research.

The project will be carried out jointly by the PTB groups Data Analysis and Measurement Uncertainty and IR-Spectrometry, as well as the group of Prof. Rühl from the Freie Universität Berlin.

[1] B. Kästner, F. Schmähling, A. Hornemann, G. Ulrich, A. Hoehl, M. Kruskopf, K. Pierz, M. B. Raschke, G. Wübbeler, and C. Elster, "Compressed sensing FTIR nano-spectroscopy and nano-imaging," Opt. Express 26, 18115 (2018).

Contact:

B. Kästner, 7.11, E-Mail: Opens window for sending emailBernd.Kaestner(at)ptb.de
C. Elster, 8.42, E-Mail: Opens window for sending emailClemens.Elster(at)ptb.de