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Updated: May 24, 2026

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
Gating the charge state of single molecules by local electric fields
I Fernández-Torrente1, D Kreikemeyer-Lorenzo, A Stróżecka
1Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
Abstract:
The electron-acceptor molecule TCNQ is found in either of two distinct integer charge states when embedded into a monolayer of a charge transfer complex on a gold surface. Scanning tunneling spectroscopy measurements identify these states through the presence or absence of a zero-bias Kondo resonance. Increasing the (tip-induced) electric field allows us to reversibly induce the oxidation or reduction of TCNQ species from their anionic or neutral ground state, respectively. We show that the different ground states arise from slight variations in the underlying surface potential, pictured here as the gate of a three-terminal device.
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