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DOE OSTI · 1902296

Temperature-driven changes in the Fermi surface of graphite

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

Here we report on temperature-dependent size and anisotropy of the Fermi pockets in graphite revealed by magnetotransport measurements. The magnetoresistances (MRs) obtained in fields along the c axis obey an extended Kohler's rule, with the carrier density following the 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 MR anisotropy in semimetals.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYFermi surfaceelectrical conductivityelectrical propertiesmagnetotransportresistivity measurementssemimetalssingle crystal materials

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Thoutam, Laxman R., Pate, Samuel E., Wang, Tingting, Wang, Yong-Lei, Divan, Ralu, Martin, Ivar, Luican-Mayer, Adina, Welp, Ulrich, Kwok, Wai-Kwong, Xiao, Zhi-Li. 2022-10-10. Temperature-driven changes in the Fermi surface of graphite. https://doi.org/10.1103/physrevb.106.155117

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