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arXiv · 1603.02603

The hole Fermi surface in Bi$_{2}$Se$_{3}$ probed by quantum oscillations

B. A. Piot·W. Desrat·D. K. Maude·M. Orlita·M. Potemski·G. Martinez·Y. S. Hor
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Abstract

Transport and torque magnetometry measurements are performed at high magnetic fields and low temperatures in a series of p-type (Ca-doped) Bi$_{2}$Se$_{3}$ crystals. The angular dependence of the Shubnikov-de Haas and de Haas-van Alphen quantum oscillations enables us to determine the Fermi surface of the bulk valence band states as a function of the carrier density. At low density, the angular dependence exhibits a downturn in the oscillations frequency between $0^\circ$ and $90^\circ$, reflecting a bag-shaped hole Fermi surface. The detection of a single frequency for all tilt angles rules out the existence of a Fermi surface with different extremal cross-sections down to $24$~meV. There is therefore no signature of a camel-back in the valence band of our bulk samples, in accordance with the direct band gap predicted by $GW$ calculations.

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B. A. Piot, W. Desrat, D. K. Maude, M. Orlita, M. Potemski, G. Martinez, Y. S. Hor. 2016-03-08. The hole Fermi surface in Bi$_{2}$Se$_{3}$ probed by quantum oscillations. https://doi.org/10.1103/physrevb.93.155206

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