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arXiv · 2301.01101

Manipulation of the magnetic state of a porphyrin-based molecule on gold: From Kondo to quantum nanomagnet via the charge fluctuation regime

Yingzheng Gao·Sergio Vlaic·Tommaso Gorni·Luca de' Medici·Sylvain Clair·Dimitri Roditchev·Stéphane Pons
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Abstract

By moving individual Fe-Porphyrin-based molecules with the tip of Scanning Tunneling Microscope in the vicinity of a Br-atom containing elbow of the herringbone-reconstructed Au(111), we reversibly and continuously control their magnetic state. Several regimes are obtained experimentally and explored theoretically: from the integer spin limit, through intermediate magnetic states with renormalized magnetic anisotropy, until the Kondo-screened regime, corresponding to a progressive increase of charge fluctuations and mixed valency due to an increase in the interaction of the molecular Fe states with the substrate Fermi sea. Our results open a route for the realization, tuning and experimental studies of novel quantum magnetic states in molecule-surface hybrids.

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Yingzheng Gao, Sergio Vlaic, Tommaso Gorni, Luca de' Medici, Sylvain Clair, Dimitri Roditchev, Stéphane Pons. 2023-01-03. Manipulation of the magnetic state of a porphyrin-based molecule on gold: From Kondo to quantum nanomagnet via the charge fluctuation regime. https://doi.org/10.1021/acsnano.2c12223

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