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arXiv · 1902.00405

Nonintrinsic origin of the magnetic-field-induced metal-insulator and electronic phase transitions in graphite

José Barzola-Quiquia·Pablo D. Esquinazi·Christian E. Precker·Markus Stiller·Mahsa Zoraghi·Tobias Förster·Thomas Herrmannsdörfer·William A. Coniglio
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Abstract

A detailed magnetoresistance study of bulk and microflake samples of highly oriented pyrolytic graphite with a thickness of 25 $\mu$m to 23~nm reveals that the usually observed field-induced metal-insulator and electronic phase transitions vanish in thinner samples. The observed suppression is accompanied by orders of magnitude decrease of the magnetoresistance and of the amplitude of the Shubnikov-de-Haas oscillations. The overall behavior is related to the decrease in the quantity of two-dimensional interfaces between crystalline regions of the same and different stacking orders present in graphite samples. Our results indicate that these field-induced transitions are not intrinsic to the ideal graphite structure and, therefore, a relevant portion of the published interpretations should be reconsidered.

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José Barzola-Quiquia, Pablo D. Esquinazi, Christian E. Precker, Markus Stiller, Mahsa Zoraghi, Tobias Förster, Thomas Herrmannsdörfer, William A. Coniglio. 2019-02-01. Nonintrinsic origin of the magnetic-field-induced metal-insulator and electronic phase transitions in graphite. https://doi.org/10.1103/physrevmaterials.3.054603

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