Quantum transport reveals spin glass correlations in a 2D network of TbPc$_{2}$ single-molecule magnets grafted on graphene

Nianjheng Wu; Jules Lefeuvre; Andrew Mayne; Stéphane Campidelli; Jérôme Lagoute; Cyril Chacon; Sophie Guéron; Richard Deblock; Hélène Bouchiat

arXiv · 2603.29456

Quantum transport reveals spin glass correlations in a 2D network of TbPc$_{2}$ single-molecule magnets grafted on graphene

Nianjheng Wu·Jules Lefeuvre·Andrew Mayne·Stéphane Campidelli·Jérôme Lagoute·Cyril Chacon·Sophie Guéron·Richard Deblock·Hélène Bouchiat

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Abstract

The low temperature magnetoresistance of graphene functionalized by an array of magnetic Terbium Phthalocyanines molecules is found to exhibit a magnetic field-dependent 1/f noise, along with universal conductance fluctuations (UCFs) typical of a mesoscopic phase-coherent sample. A thorough analysis of the magnetic field, temperature and chemical potential dependence of this 1/f noise and UCFs reveals that long range, 2D Ising spin-glass like, magnetic correlations are induced in graphene through exchange interactions between the magnetic molecules and charge carriers in graphene. These experiments show that graphene functionalized with organic molecules constitutes a versatile platform for the investigation of magnetic phase transitions in two dimensions.

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Nianjheng Wu, Jules Lefeuvre, Andrew Mayne, Stéphane Campidelli, Jérôme Lagoute, Cyril Chacon, Sophie Guéron, Richard Deblock, Hélène Bouchiat. 2026-03-31. Quantum transport reveals spin glass correlations in a 2D network of TbPc$_{2}$ single-molecule magnets grafted on graphene. https://arxiv.org/abs/2603.29456

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