The superconductivity and nontrivial topological electronic state are key hallmarks of topological superconductors.Here,we focus on the transport signals of possible topological surface state in the topological superc...The superconductivity and nontrivial topological electronic state are key hallmarks of topological superconductors.Here,we focus on the transport signals of possible topological surface state in the topological superconductor candidate β-PdBi_(2) nanoflake with a thickness of 21 nm.The resistance demonstrates a semiconductor-metal transition followed by an upturned behavior as the temperature decreases.A large and unsaturated longitudinal magnetoresistance(MR),accompanied by distinct Shubnikov-de Hass oscillation in Hall resistance,is observed.An analysis of Hall resistance reveals that the carriers present the characteristics of relativistic particles with small effective mass and extremely high mobility.The angle-dependent quantum oscillations demonstrate a two-dimensional Fermi surface topology.A giant anisotropic MR as large as 98%is detected when rotating the magnetic field.These results provide the possible transport signals of a nontrivial topological electronic state,establishing a further understanding of the topological properties of the low-dimensional topological superconductor candidate β-PdBi_(2).展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.U19A2093,11904002,and U2032163)the National Key Research and Development Program of China(Grant No.2021YFA1600201)the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2021117)。
文摘The superconductivity and nontrivial topological electronic state are key hallmarks of topological superconductors.Here,we focus on the transport signals of possible topological surface state in the topological superconductor candidate β-PdBi_(2) nanoflake with a thickness of 21 nm.The resistance demonstrates a semiconductor-metal transition followed by an upturned behavior as the temperature decreases.A large and unsaturated longitudinal magnetoresistance(MR),accompanied by distinct Shubnikov-de Hass oscillation in Hall resistance,is observed.An analysis of Hall resistance reveals that the carriers present the characteristics of relativistic particles with small effective mass and extremely high mobility.The angle-dependent quantum oscillations demonstrate a two-dimensional Fermi surface topology.A giant anisotropic MR as large as 98%is detected when rotating the magnetic field.These results provide the possible transport signals of a nontrivial topological electronic state,establishing a further understanding of the topological properties of the low-dimensional topological superconductor candidate β-PdBi_(2).
