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arXiv · 1501.00413

Transport Signatures of Fermi Surface Topology Change in BiTeI

Linda Ye·Joseph G. Checkelsky·Fumitaka Kagawa·Yoshinori Tokura
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Abstract

We report a quantum magnetotransport signature of a change in Fermi surface topology in the Rashba semiconductor BiTeI with systematic tuning of the Fermi level $E_F$. Beyond the quantum limit, we observe a marked increase/decrease in electrical resistivity when $E_F$ is above/below the Dirac node that we show originates from the Fermi surface topology. This effect represents a measurement of the electron distribution on the low-index ($n=0,-1$) Landau levels and is uniquely enabled by the finite bulk $k_z$ dispersion along the $c$-axis and strong Rashba spin-orbit coupling strength of the system. The Dirac node is independently identified by Shubnikov-de Haas oscillations as a vanishing Fermi surface cross section at $k_z=0$. Additionally we find that the violation of Kohler's rule allows a distinct insight into the temperature evolution of the observed quantum magnetoresistance effects.

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Linda Ye, Joseph G. Checkelsky, Fumitaka Kagawa, Yoshinori Tokura. 2015-01-02. Transport Signatures of Fermi Surface Topology Change in BiTeI. https://doi.org/10.1103/physrevb.91.201104

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