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Updated: Nov 20, 2025
Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Topological semimetal state with triply degenerate nodal points in a stable Cu2Te structure
1Surface Physics Laboratory (National Key Laboratory), Key Laboratory of Computational Physical Sciences (MOE), Department of Physics and Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, People's Republic of China. 12110190073@fudan.edu.cn and School of Mathematics, Physics and Statistics, Shanghai University of Engineering Science, Shanghai 201620, People's Republic of China.
Abstract:
Cu2Te is commonly used as the backside contact of CdTe-based solar cells. We predict a stable topological semimetal structure of Cu2Te(R3m) with triply degenerate nodal points near the Fermi energy. Triply degenerate nodal points are formed by the band crossing between two states with angular momentum j equal to 3/2 and 1/2 along the unique C3 axis. The anisotropic strain breaking C3 symmetry opens the energy gap, and transforms semimetal Cu2Te(R3m) into a topological insulator. It provides strong evidence for understanding the unconventional large linear magnetoresistance in Cu2-xTe. The band crossing of Cu2Te(R3m) strongly depends on the orbital on-site energy difference and the SOC strength. Crystal structures with the space group R3m (no. 160) are a good platform to obtain topological semimetals with triply degenerate nodal points. Compounds X2Y (X = Cu, Ag, Au, Y = O, S, Se, Te) except for Au2S and Cu2O are topological semimetals with triply degenerate nodal points around the Fermi energy.
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