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arXiv · 1806.08139

Extremely large magnetoresistance and the complete determination of the Fermi surface topology in the semimetal ScSb

Abstract

We report the magnetoresistance of ScSb, which is a semimetal with a simple rocksalt-type structure. We found that the magnetoresistance reaches $\sim$28000 % at 2 K and 14 T in our best sample, and it exhibits a resistivity plateau at low temperatures. The Shubnikov-de Haas oscillations extracted from the magnetoresistance data allow the full construction of the Fermi surface, including the so-called $α_3$ pocket which has been missing in other closely related monoantimonides, and an additional hole pocket centered at $Γ$. The electron concentration ($n$) and the hole concentration ($p$) are extracted from our analysis, which indicate that ScSb is a nearly compensated semimetal with $n/p\approx0.93$. The calculated band structure indicates the absence of a band inversion, and the large magnetoresistance in ScSb can be attributed to the nearly perfect compensation of electrons and holes, despite the existence of the additional hole pocket.

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Y. J. Hu, E. I. Paredes Aulestia, K. F. Tse, C. N. Kuo, J. Y. Zhu, C. S. Lue, K. T. Lai, Swee K. Goh. 2018-08-07. Extremely large magnetoresistance and the complete determination of the Fermi surface topology in the semimetal ScSb. https://doi.org/10.1103/physrevb.98.035133

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