Bulk Fermi surface of the layered superconductor TaSe3 with three-dimensional strong topological state

Autor: Linchao Ding, Zengwei Zhu, Weiwei Zhao, Leiming Chen, Li Pi, Yanfeng Guo, Yufeng Hao, Xianbiao Shi, Xufeng Kou, Wei Xia, Yong Zhang, Zhiqiang Zou, Bin Li, Na Yu, Qin Wang, Hao Su, Xia Wang
Rok vydání: 2020
Předmět:
Zdroj: Physical Review B. 101
ISSN: 2469-9969
2469-9950
Popis: High-magnetic-field transport measurements and ab initio calculations on the layered superconductor TaSe3 have provided evidence for the existence of a three-dimensional strong topological state. Longitudinal magnetotransport measurements up to similar to 33 T unveiled striking Shubnikov-de Haas oscillations with two fundamental frequencies at 100 and 175 T corresponding to a nontrivial hole Fermi pocket at the Gamma point and a nontrivial electron Fermi pocket at the B point, respectively, in the Brillouin zone. However, calculations revealed one more electron pocket at the B point which was not detected by the magnetotransport measurements, presumably due to the limited carrier momentum relaxation time. Angle-dependent quantum oscillations by rotating the sample with respect to the magnetic field revealed clear changes in the two fundamental frequencies, indicating anisotropic electronic Fermi pockets. The ab initio calculations gave the topological Z(2) invariant of (1; 100) and revealed a single Dirac cone on the (1 0 -1) surface at the (X) over bar point with helical spin texture at a constant energy contour, suggesting a strong topological state. The results demonstrate TaSe3 as an excellent platform to study the interplay between the topological phase and superconductivity and a promising system for the exploration of topological superconductivity.
Databáze: OpenAIRE