Anisotropic magnetoresistance and quantum oscillation in Sb2Te3 single crystal synthesized by a Te-flux method

Topological insulators (TIs) have attracted the widespread attentions due to their unique electronic struc-tures and novel physical properties in past decades. Here, we investigate the magnetoresistance (MR) and Shubnikov-de Haas (SdH) oscillation in topological Sb2Te3. It is found that the angle-dependent MR shows the obvious anisotropy, and the maximal MR reaches similar to 220% with the magnetic field rotated in ab plane at 2.5 K and 9 T. The Landau-level fan diagram indicates that Sb2Te3 possesses a nontrivial Berry phase. Comparing the SdH oscillations measured by the magnetic fields rotated in bc and ab planes, we find that the oscillation frequencies are similar, and the Berry phase shift is very slight. The first-principles calcu-lations demonstrate that Sb vacancy can introduce an additional band across the Fermi level. The anisotropy of the Fermi surfaces reveals the anisotropic MR. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

In this study, the magnetoresistance (MR) and Shubnikov-de Haas (SdH) oscillation in topological Sb2Te3 were investigated. The results showed obvious anisotropy in angle-dependent MR and revealed the presence of a nontrivial Berry phase. It was also found that Sb vacancies can introduce an additional band, leading to anisotropic Fermi surfaces and magnetoresistance.