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Updated: May 8, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Electroisomerization blinking of an azobenzene derivative molecule
Sylvie Godey1, Hugo Therssen1, David Guérin1
1University Lille, CNRS, University Polytechnique Hauts-de-France, UMR 8520-IEMN-Institut d'Electronique de Microélectronique et de Nanotechnologie, F-59000 Lille, France.
Abstract:
We report here the reversibility and bistability of the switching behavior in an azobenzene derivative induced by the bias applied by a scanning-tunneling microscopy (STM) tip, at low temperature and in ultra-high vacuum environment. Thiscis-to-transandtrans-to-cisswitching were observed during STM imaging in either polarity at +2 V or -2 V, on a sub-second time scale. This results in a blinking effect visible on STM images, corresponding to the reversible switching of the azobenzene molecule under the applied STM bias through an electric field induced process.
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