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arXiv · 2209.08406

Temperature-driven changes in the Fermi surface of graphite

Laxman R. Thoutam·Samuel E. Pate·Tingting Wang·Yong-Lei Wang·Ralu Divan·Ivar Martin·Adina Luican-Mayer·Ulrich Welp·Wai-Kwong Kwok·Zhi-Li Xiao
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Abstract

We report on temperature-dependent size and anisotropy of the Fermi pockets in graphite revealed by magnetotransport measurements. The magnetoresistances obtained in fields along the c-axis obey an extended Kohler's rule, with the carrier density following prediction of a temperature-dependent Fermi energy, indicating a change in the Fermi pocket size with temperature. The angle-dependent magnetoresistivities at a given temperature exhibit a scaling behavior. The scaling factor that reflects the anisotropy of the Fermi surface is also found to vary with temperature. Our results demonstrate that temperature-driven changes in Fermi surface can be ubiquitous and need to be considered in understanding the temperature-dependent carrier density and magnetoresistance anisotropy in semimetals.

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Laxman R. Thoutam, Samuel E. Pate, Tingting Wang, Yong-Lei Wang, Ralu Divan, Ivar Martin, Adina Luican-Mayer, Ulrich Welp, Wai-Kwong Kwok, Zhi-Li Xiao. 2022-09-17. Temperature-driven changes in the Fermi surface of graphite. https://doi.org/10.1103/physrevb.106.155117

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