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arXiv · 2003.13397

Quantum oscillations and electronic structure in the large-Chern number topological chiral semimetal PtGa

Sheng Xu·Liqin Zhou·Xiao-Yan Wang·Huan Wang·Jun-Fa lin·Xiang-Yu Zeng·Peng Cheng·Hongming Weng·Tian-Long Xia
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Abstract

We report the magnetoresistance(MR), de Haas-van Alphen (dHvA) oscillations and the electronic structures of single crystal PtGa. The large unsaturated MR is observed with the magnetic field B//[111]. Evident dHvA oscillations with B//[001] configuration have been observed, from which twelve fundamental frequencies are extracted and the spin-orbit coupling effect (SOC) induced band splitting is revealed. The light cyclotron effective masses are extracted from the fitting by the thermal damping term of the Lifshitz-Kosevich (LK) formula. Combining with the calculated frequencies from the first-principles calculations, the dHvA frequencies F$_1$/F$_3$ and F$_{11}$/F$_{12}$ are confirmed to originate from the electron pockets at $\Gamma$ and R, respectively. The first-principles calculations also reveal the existence of spin-3/2 RSW fermion and time-reversal (TR) doubling of the spin-1 excitation at $\Gamma$ and R with large Chern number $\pm4$ when SOC is included.

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Sheng Xu, Liqin Zhou, Xiao-Yan Wang, Huan Wang, Jun-Fa lin, Xiang-Yu Zeng, Peng Cheng, Hongming Weng, Tian-Long Xia. 2020-03-30. Quantum oscillations and electronic structure in the large-Chern number topological chiral semimetal PtGa. https://doi.org/10.1088/0256-307x%2F37%2F10%2F107504

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