Investigation of Angle‐Dependent Shubnikov‐de Haas Oscillations in Topological Insulator Bismuth

Abstract

The current article investigates the band structure in the presence and absence of spin‐orbit coupling (SOC), examines the Z2 invariants, and investigates the detailed angle‐dependent magneto‐transport of up to 10 T (Tesla) and down to 2 K for the bismuth crystal. The out‐of‐plane field‐dependent magnetoresistance (MR) is positive and is huge to the order of ≈104% at 2 K and 10 T. On the contrary, the longitudinal (in‐plane) field‐dependent MR is relatively small and is negative. The thermal activation energy is also estimated by using the Boltzmann formula from resistivity versus temperature measurement under applied transverse magnetic fields. The topological nature of Bi is confirmed by Z2 invariant calculation using density functional theory (DFT). PBESol bands show trivial but hybrid functional (HSE) bands show non‐trivial topology being present in Bismuth. This article comprehensively studies the dependence of MR oscillations upon the angle between the applied field and the current. The observed oscillations fade away as the angle is increased. This article is an extension of our previous work on bismuth (J. Sup. Novel Mag. 2023, 36, 389), in which a comprehensive analysis of its structural and micro‐structural properties is conducted along with its transport behavior in an applied transverse magnetic field.