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

ZITKO, R.; BLESIO, G. G.; MANUEL, L. O.; ALIGIA, A. A.

NATURE COMMUNICATIONS

Springer Nature

Año: 2021 vol. 12

2041-1723

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