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arXiv · 1411.3323

Charge density waves in graphite; towards the magnetic ultra-quantum limit

F. Arnold·A. Isidori·E. Kampert·B. Yager·M. Eschrig·J. Saunders
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Abstract

Graphite is a model system for the study of three-dimensional electrons and holes in the magnetic quantum limit, in which the charges are confined to the lowest Landau levels. We report magneto-transport measurements in pulsed magnetic fields up to 60 T, which resolve the collapse of two density wave states in two, electron and hole, Landau levels at 52.3 and 54.2 T respectively. We report evidence for a commensurate density wave at 47.1 T in the electron Landau level. The theoretical modelling of these results predicts that the ultra-quantum limit is entered above 73.5 T. This state is an insulator, and we discuss its correspondence to the "metallic" state reported earlier. We propose that this (interaction-induced) insulating phase supports surface states that carry no charge or spin within the planes, but does however support charge transport out of plane.

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F. Arnold, A. Isidori, E. Kampert, B. Yager, M. Eschrig, J. Saunders. 2017-04-24. Charge density waves in graphite; towards the magnetic ultra-quantum limit. https://doi.org/10.1103/physrevlett.119.136601

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