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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Vibronic Spectroscopy with Submolecular Resolution from STM-Induced Electroluminescence
Benjamin Doppagne1, Michael C Chong1, Etienne Lorchat1
1Université de Strasbourg, CNRS, IPCMS, UMR 7504, F-67000 Strasbourg, France.
Physical Review Letters
|April 8, 2017
Summary
Scanning tunneling microscopy reveals molecular vibrations in phthalocyanine using electroluminescence. This technique provides a chemical fingerprint and submolecular imaging of molecules, detailing their structure and symmetry.
Area of Science:
- Surface Science
- Molecular Spectroscopy
- Nanotechnology
Background:
- Phthalocyanine molecules are widely studied for their electronic and optical properties.
- Scanning tunneling microscopy (STM) enables atomic-scale surface characterization.
Purpose of the Study:
- To investigate the electroluminescence of phthalocyanine molecules using STM.
- To correlate spectroscopic features with molecular vibrational modes.
- To achieve submolecular resolution imaging of molecular vibrations.
Main Methods:
- Utilized a scanning tunneling microscope (STM) to induce and detect electroluminescence.
- Acquired photon spectra of the emitted light.
- Compared electroluminescence spectra with Raman spectra from bulk phthalocyanine crystals.
- Generated spatial maps of vibronic features.
Main Results:
- Observed an intense emission line at approximately 1.9 eV, attributed to phthalocyanine fluorescence.
- Identified weaker, redshifted lines corresponding to molecular vibrational modes.
- Established a spectroscopic fingerprint for chemical identification.
- Revealed submolecularly resolved structures in vibronic maps related to vibrational mode symmetry.
Conclusions:
- STM-induced electroluminescence is a viable method for probing molecular vibrations.
- This technique offers a chemical fingerprint and submolecular structural information.
- The study demonstrates the potential for detailed chemical and structural analysis of molecules on surfaces.
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