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arXiv · 1807.00865

Electronic structure of topological superconductor candidate Au${}_{2}$Pb

Yun Wu·Gil Drachuck·Lin-Lin Wang·Duane. D. Johnson·Przemyslaw Swatek·Benjamin Schrunk·Daixiang Mou·Lunan Huang·S. L. Bud'ko·P. C. Canfield·Adam Kaminski
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Abstract

We use magnetization measurements, high-resolution angle-resolved photoemission spectroscopy (ARPES), and density functional theory (DFT) calculations to study the electronic properties of Au${}_{2}$Pb, a topological superconductor candidate. The magnetization measurements reveal three discontinuities at 40, 51, and 99~K that agree well with reported structural phase transitions. ARPES measurements of the Au${}_{2}$Pb (111) surface at 110~K shows a shallow hole pocket at the center and flower-petal-like surface states at the corners of the Brillouin zone. These observations match the results of DFT calculations relatively well. The flower-petal-like surface states appear to originate from a Dirac like dispersion close to the zone corner. For the Au${}_{2}$Pb (001) surface at 150~K, ARPES reveals at least one electron pocket between the $\Gamma$ and $M$ points, consistent with the DFT calculations. Our results provide evidence for the possible existence of Dirac state in this material.

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Yun Wu, Gil Drachuck, Lin-Lin Wang, Duane. D. Johnson, Przemyslaw Swatek, Benjamin Schrunk, Daixiang Mou, Lunan Huang, S. L. Bud'ko, P. C. Canfield, Adam Kaminski. 2018-07-02. Electronic structure of topological superconductor candidate Au${}_{2}$Pb. https://doi.org/10.1103/physrevb.98.161107

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