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arXiv · 2311.01496

Noncoplanar and chiral spin states on the way towards N\'eel ordering in fullerene Heisenberg models

Attila Szabó·Sylvain Capponi·Fabien Alet
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Abstract

Using high-accuracy variational Monte Carlo based on group-convolutional neural networks (GCNNs), we obtain the symmetry-resolved low-energy spectrum of the spin-1/2 Heisenberg model on several highly symmetric fullerene geometries, including the famous C$_{60}$ buckminsterfullerene. We argue that as the degree of frustration is lowered in large fullerenes, they display characteristic features of incipient magnetic ordering: correlation functions show high-intensity Bragg peaks consistent with N\'eel-like ordering, while the low-energy spectrum is organised into a tower of states. Competition with frustration, however, turns the simple N\'eel order into a noncoplanar one. Remarkably, we find and predict chiral incipient ordering in a large number of fullerene structures.

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Attila Szabó, Sylvain Capponi, Fabien Alet. 2023-11-02. Noncoplanar and chiral spin states on the way towards N\'eel ordering in fullerene Heisenberg models. https://doi.org/10.1103/physrevb.109.054410

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