Corrugation in a molecular C60 monolayer as a frustrated magnet

M. Alfonso-Moro; V. Guisset; P. David; B. Canals; J. Coraux; N. Rougemaille

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arXiv · 2302.01652

Corrugation in a molecular C60 monolayer as a frustrated magnet

M. Alfonso-Moro·V. Guisset·P. David·B. Canals·J. Coraux·N. Rougemaille

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Abstract

Under certain experimental conditions, the deposition of C60 molecules onto an atomically flat copper surface gives rise to the formation of corrugated islands. This corrugation, which reflects a molecular displacement perpendicular to the surface plane, presents an astonishing pattern: it is well described by a frustrated Ising spin Hamiltonian whose thermodynamics is compatible with a spin liquid about to transit towards an ordered zigzag state. Here we study the statistical properties of such a molecular corrugation using tools generally employed in frustrated magnetism. More specifically, the real and reciprocal space analysis of pairwise molecule correlations allows us to demonstrate that the C60/Cu system, in which magnetism is totally absent, has all the characteristics of a triangular Ising antiferromagnet. Our results indicate that the organization of two-dimensional matter, at the molecular length scale, sometimes turns out to be particularly close to that encountered in highly frustrated magnets.

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M. Alfonso-Moro, V. Guisset, P. David, B. Canals, J. Coraux, N. Rougemaille. 2023-02-03. Corrugation in a molecular C60 monolayer as a frustrated magnet. https://arxiv.org/abs/2302.01652

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