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arXiv · 2312.17143

Coexistence of Dirac fermion and charge density wave in square-net-based semimetal LaAuSb2

Xueliang Wu·Zhixiang Hu·David Graf·Yu Liu·Chaoyue Deng·Huixia Fu·Asish K. Kundu·Tonica Valla·Cedomir Petrovic·Aifeng Wang
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Abstract

We report a comprehensive study of magnetotransport properties, angle-resolved photoemission spectroscopy (ARPES), and density functional theory (DFT) calculations on self-flux grown LaAuSb$_2$ single crystals. Resistivity and Hall measurements reveal a charge density wave (CDW) transition at 77 K. MR and de Haas-Van Alphen (dHvA) measurements indicate that the transport properties of LaAuSb$_2$ are dominated by Dirac fermions that arise from Sb square nets. ARPES measurements and DFT calculations reveal an electronic structure with a common feature of the square-net-based topological semimetals, which is in good agreement with the magnetotransport properties. Our results indicate the coexistence of CDW and Dirac fermion in LaAuSb$_2$, both of which are linked to the bands arising from the Sb-square net, suggesting that the square net could serve as a structural motif to explore various electronic orders.

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Xueliang Wu, Zhixiang Hu, David Graf, Yu Liu, Chaoyue Deng, Huixia Fu, Asish K. Kundu, Tonica Valla, Cedomir Petrovic, Aifeng Wang. 2023-12-28. Coexistence of Dirac fermion and charge density wave in square-net-based semimetal LaAuSb2. https://doi.org/10.1103/physrevb.108.245156

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