06. 04. 2023 13:00

Mgr. Martin Švec, Ph.D. » Light, tips and molecules: SPM on the path to direct nano-optical measurements

Institute of Physics, Czech Academy of Sciences

Mgr. Martin Švec, Ph.D.

Online link: www.fzu.cz

Attachement:

Location: Seminar room F 052, Ke Karlovu 5, 121 16 Praha 2

Exploration of essential photophysical phenomena at the level of individual quantum objects requires
highly specialized optical spectroscopies. These techniques require working at the very limit of
instrument sensitivity or the use of plasmonic nanostructures - in order to overcome the fundamental
resolution limits achievable with visible and infrared light. The recent developments emerging in the
field of Scanning Probe Light Microscopy bring the unique opportunity to pursue intriguing, often
hard-to-access interactions between light and matter at submolecular scale, with the finesse
characteristic for the method based on atomically-sharp tips. The plasmonic nanocavity formed
naturally between the tip and sample enables massive enhancement of the light field coupling to the
studied objects, and therefore visualization of the fascinating photophysics within nanoscopic emitters.
The modes of operation can be switched between the electroluminescence, photoluminescence and
tip-enhanced Raman spectroscopies. The addition of the toolbox of cryogenic STM, STS and AFM
provides a reliable support in questions of the system geometry and electronic configuration.1 As the
emitted photons and their spectra carry a rich information about the eigenmodes, charges, vibronics
and temporal evolution of the transient states, we can build a detailed picture of the cycles comprising
the process of single-photon generation, tracing the relevant energy conversion pathways,2
quasiparticle delocalization over excitonic nanoclusters,3 interaction with electrical fields and vibronic
coupling to electronic transitions.4

[1] Charge carrier injection electroluminescence with CO functionalized tips on single molecular emitters. J. Doležal, P. Merino, J. Redondo, L. Ondič, A. Cahlík and M. Švec, Nano Lett. 19, 8605-861 (2019)
[2] Exciton-Trion Conversion Dynamics in a Single Molecule. J Doležal, S Canola, P Merino and M. Švec, ACS Nano 15, 7694–7699 (2021)
[3] Real space visualization of entangled excitonic states in charged molecular assemblies. J Doležal, S. Canola, P. Hapala, R. Ferreira, P Merino and M Švec, ACS Nano 16, 1082-1088 (2022)
[4] Evidence of trion-libron coupling in chirally adsorbed single molecules. J. Doležal, S. Canola, P. Hapala, RCC Ferreira, P. Merino, M. Švec, Nature Comm. 13, 6008 (2022)

 

Seminar on Condensed Matter Theory

Group of Theoretical Physics organizes a regular seminar on theory of condensed matter physics.

Usually, we meet
every Thursdays at 13:00
in seminar room F 052
Ke Karlovu 5, 121 16 Praha 2.

You are welcome to join us!

If you wish to receive regular updates on fothcoming seminars, contact K. Carva.