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Electronic Characterization of a Charge-Transfer Complex Monolayer on Graphene.

ABSTRACT: Organic charge-transfer complexes (CTCs) formed by strong electron acceptor and strong electron donor molecules are known to exhibit exotic effects such as superconductivity and charge density waves. We present a low-temperature scanning tunneling microscopy and spectroscopy (LT-STM/STS) study of a two-dimensional (2D) monolayer CTC of tetrathiafulvalene (TTF) and fluorinated tetracyanoquinodimethane (F₄TCNQ), self-assembled on the surface of oxygen-intercalated epitaxial graphene on Ir(111) (G/O/Ir(111)). We confirm the formation of the charge-transfer complex by dI/dV spectroscopy and direct imaging of the singly occupied molecular orbitals. High-resolution spectroscopy reveals a gap at zero bias, suggesting the formation of a correlated ground state at low temperatures. These results point to the possibility to realize and study correlated ground states in charge-transfer complex monolayers on weakly interacting surfaces.

SUBMITTER: Kumar A

PROVIDER: S-EPMC8223480 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Electronic Characterization of a Charge-Transfer Complex Monolayer on Graphene.

Kumar Avijit A Banerjee Kaustuv K Ervasti Mikko M MM Kezilebieke Shawulienu S Dvorak Marc M Rinke Patrick P Harju Ari A Liljeroth Peter P

ACS nano 20210524 6

Organic charge-transfer complexes (CTCs) formed by strong electron acceptor and strong electron donor molecules are known to exhibit exotic effects such as superconductivity and charge density waves. We present a low-temperature scanning tunneling microscopy and spectroscopy (LT-STM/STS) study of a two-dimensional (2D) monolayer CTC of tetrathiafulvalene (TTF) and fluorinated tetracyanoquinodimethane (F<sub>4</sub>TCNQ), self-assembled on the surface of oxygen-intercalated epitaxial graphene on ...[more]

PMID: 34028269

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