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arXiv · 2205.10476

Topological quantum phase transition of nickelocene on Cu(100)

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

Local quantum phase transitions driven by Kondo correlations have been theoretically proposed in several magnetic nanosystems; however, clear experimental signatures are scant. Modeling a nickelocene molecule on a Cu(100) substrate as a two-orbital Anderson impurity with single-ion easy-plane anisotropy coupled to two conduction bands, we find that recent scanning tunneling spectra measured at different microscope tip heights reveal the existence of a topological quantum phase transition from the usual local Fermi liquid with high zero-bias conductance to a non-Landau Fermi liquid, characterized by a non-trivial quantized Luttinger integral, with a small conductance. The effects of intermediate valence, finite temperature, and structural relaxation of the molecule position allow us to explain the different observed behaviors.

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G. G. Blesio, R. Žitko, L. O. Manuel, A. A. Aligia. 2023-01-18. Topological quantum phase transition of nickelocene on Cu(100). https://arxiv.org/abs/2205.10476

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