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Thermoelectric nanospectroscopy for the imaging of molecular fingerprints


A nanospectroscopic device platform has been developed for the thermoelectric detection of molecular fingerprints of soft materials at nanometer scale spatial resolution. The technique makes use of a locally generated thermal gradient converted into a thermoelectric voltage that is read out in the underlying device. The thermal gradient is generated by an illuminated atomic force microscope tip that localizes power absorption onto the sample surface.

The sensor provides an alternative detection principle for nanospectroscopic imaging, which requires both, large bandwidth and high sensitivity at the same time. Usually, nitrogen cooled photoconductive elements are used for this application. The thermoelectric sensor operates at room temperature and in contrast to photoconductive detectors does not suffer from spectral range limitations.

The development was performed in collaboration with the University of Cambridge, University of Regensburg and Freie Universität Berlin.

Publication: G. Ulrich, E. Pfitzner, A. Hoehl, J.-W. Liao, O. Zadvorna, G. Schweicher, H. Sirringhaus, J. Heberle, B. Kästner, J. Wunderlich, and D. Venkateshvaran, "Thermoelectric nanospectroscopy for the imaging of molecular fingerprints," Nanophotonics 9,  4347–4354 (2020); doi.org/10.1515/nanoph-2020-0316.


B. Kästner, 7.11, E-Mail: Opens local program for sending emailBernd.Kaestner(at)ptb.de