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arXiv · 2105.13248

Iron phthalocyanine on Au(111) is a "non-Landau" Fermi liquid

R. Žitko·G. G. Blesio·L. O. Manuel·A. A. Aligia
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Abstract

The paradigm of Landau's Fermi liquid theory has been challenged with the finding of a strongly interacting Fermi liquid that cannot be adiabatically connected to a non-interacting system. A spin-1 two-channel Kondo impurity with anisotropy D has a quantum phase transition between two topologically different Fermi liquids with a peak (dip) in the Fermi level for D < Dc (D > Dc). Extending this theory to general multi-orbital problems with finite magnetic field, we reinterpret in a unified and consistent fashion several experimental studies of iron phthalocyanine molecules on Au(111) that were previously described in disconnected and conflicting ways. The differential conductance shows a zero-bias dip that widens when the molecule is lifted from the surface (reducing the Kondo couplings) and is transformed continuously into a peak under an applied magnetic field. We reproduce all features and propose an experiment to induce the topological transition.

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R. Žitko, G. G. Blesio, L. O. Manuel, A. A. Aligia. 2021-05-27. Iron phthalocyanine on Au(111) is a "non-Landau" Fermi liquid. https://doi.org/10.1038/s41467-021-26339-z

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