Evidence of a room-temperature quantum spin Hall edge state in a higher-order topological insulator

Shumiya, Nana; Hossain, Md Shafayat; Yin, Jia-Xin; Wang, Zhiwei; Litskevich, Maksim; Yoon, Chiho; Li, Yongkai; Yang, Ying; Jiang, Yu-Xiao; Cheng, Guangming; Lin, Yen-Chuan; Zhang, Qi; Cheng, Zi-Jia; Cochran, Tyler A; Multer, Daniel; Yang, Xian P; Casas, Brian; Chang, Tay-Rong; Neupert, Titus; Yuan, Zhujun

doi:10.1038/s41563-022-01304-3

Citations

Citation copied

Shumiya, N., Hossain, M. S., Yin, J.-X., Wang, Z., Litskevich, M., Yoon, C., Li, Y., Yang, Y., Jiang, Y.-X., Cheng, G., Lin, Y.-C., Zhang, Q., Cheng, Z.-J., Cochran, T. A., Multer, D., Yang, X. P., Casas, B., Chang, T.-R., Neupert, T., … Hasan, M. Z. (2022). Evidence of a room-temperature quantum spin Hall edge state in a higher-order topological insulator. Nature Materials, 21(10), 1111–1115. https://doi.org/10.1038/s41563-022-01304-3

Abstract

Room-temperature realization of macroscopic quantum phases is one of the major pursuits in fundamental physics1,2. The quantum spin Hall phase3-6 is a topological quantum phase that features a two-dimensional insulating bulk and a helical edge state. Here we use vector magnetic field and variable temperature based scanning tunnelling microscopy to provide micro-spectroscopic evidence for a room-temperature quantum spin Hall edge state on the surface of the higher-order topological insulator Bi4Br4. We find that the atomically resolved