标题：Discovery of Two-Dimensional Quantum Spin Hall Effect in Triangular Transition-Metal Carbides
作者：Zhang, Shou-juan; Ji, Wei-xiao; Zhang, Chang-wen; Zhang, Shu-feng; Li, Ping; Li, Sheng-shi; Yan, Shi-shen
作者机构：[Zhang, Shou-juan; Ji, Wei-xiao; Zhang, Chang-wen; Zhang, Shu-feng; Li, Ping] Univ Jinan, Sch Phys & Technol, Jinan 250022, Shandong, Peoples R China. 更多
通讯作者：Zhang, CW;Yan, SS
通讯作者地址：[Zhang, CW]Univ Jinan, Sch Phys & Technol, Jinan 250022, Shandong, Peoples R China;[Yan, SS]Shandong Univ, Sch Phys, State Key Lab Crystal Mat, Jinan 更多
来源：CHINESE PHYSICS LETTERS
摘要：Though the quantum spin Hall effect (QSHE) in two-dimensional (2D) crystals has been widely explored, the experimental realization of quantum transport properties is only limited to HgTe/CdTe or InAs/GaSb quantum wells. Here we employ a tight-binding model on the basis of d(z2), d(xy), and d(x2-y2) orbitals to propose QSHE in the triangular lattice, which are driven by a crossing of electronic bands at the Gamma point. Remarkably, 2D oxidized Mxenes W2M2C3 are ideal materials with nontrivial gap of 0.12 eV, facilitating room-temperature observations in experiments. We also find that the nontrivially topological properties of these materials are sensitive to the cooperative effect of the electron correlation and spin-orbit coupling. Due to the feasible exfoliation from its 3D MAX phase, our work paves a new direction towards realizing QSHE with low dissipation.