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arXiv · 1108.4259

EPR study of nano-structured graphite

Jonas Kausteklis·Pavel Cevc·Denis Arcon·Lucia Nasi·Daniele Pontiroli·Marcello Mazzani·Mauro Ricco
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Abstract

We report on a systematic temperature dependent X-band electron paramagnetic resonance (EPR) study of nano-sized graphite particles prepared by ball-milling. In as-prepared samples a very intense and sharp EPR resonance at $g=2.0035$ has been measured. The EPR linewidth shows a Korringa-like linear temperature dependence arising due to the coexistence and strong exchange coupling of itinerant and localized edge states. With a prolonged aging in inert atmosphere changes in the EPR signal suggest gradual structural reconstruction where the localized edge-states dominate the EPR signal. In this case the EPR spin susceptibility shows a maximum at $\approx 23\, {\rm K}$ indicating the development of antiferromagnetic correlations as expected for the graphene lattice with a bipartite symmetry.

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Jonas Kausteklis, Pavel Cevc, Denis Arcon, Lucia Nasi, Daniele Pontiroli, Marcello Mazzani, Mauro Ricco. 2011-08-22. EPR study of nano-structured graphite. https://arxiv.org/abs/1108.4259

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