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arXiv · 2210.00126

Many-body description of STM-induced fluorescence of charged molecules

Song Jiang·Tomas Neuman·Remi Bretel·Alex Boeglin·Fabrice Scheurer·Eric Le Moal·Guillaume Schull
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Abstract

A scanning tunneling microscope is used to study the fluorescence of a model charged molecule (quinacridone) adsorbed on a sodium chloride (NaCl)-covered metallic sample. Fluorescence from the neutral and positively charged species is reported and imaged using hyper-resolved fluorescence microscopy. A many-body excitation model is established based on a detailed analysis of voltage, current and spatial dependencies of the fluorescence and electron transport features. This model reveals that quinacridone adopts a large palette of charge states, transient or not, depending on the voltage used and the nature of the underlying substrate. This model has a universal character and explains the electronic and fluorescence properties of many other molecules adsorbed on thin insulators.

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Song Jiang, Tomas Neuman, Remi Bretel, Alex Boeglin, Fabrice Scheurer, Eric Le Moal, Guillaume Schull. 2022-09-30. Many-body description of STM-induced fluorescence of charged molecules. https://doi.org/10.1103/physrevlett.130.126202

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