Correlation between changeover from weak antilocalization (WAL) to weak localization (WL) and positive to negative magnetoresistance in S-doped Bi1.5Sb0.5Te1.3Se1.7

Abstract

The magneto-transport and angle-resolved photoelectron spectroscopy (ARPES) of the S-doped Bi1.5Sb0.5Te1.3Se1.7 system have been investigated. Both the positive magnetoresistance (pMR) and negative magnetoresistance (nMR) under a perpendicular magnetic field as well as a changeover from weak antilocalization (WAL) to weak localization (WL) are observed. The interplay between pMR and nMR is elucidated in terms of the dephasing and spin–orbit scattering time scales. The topological surface state bands have been explored using ARPES.

Magnetotransport Study of Dirac Metal FeSn Thin Films Grown on Silicon Substrates

“…Figure 6 and 7 display the MR as a function of the magnetic field applied parallel and perpendicular to the direction of current flow in magnetic fields up to AE5 T measured at different temperatures between 5 and 300 K inclusive. In some topological materials with prominent spin-orbit coupling, a weak antilocalization effect with the positive quantum correction to the resistance at a low-magnetic field may be observed, resulting in a positive MR. [17] Our results have shown a small quadratic MR in both parallel and perpendicular magnetic fields for all the measured temperatures, consistent with the orbital origin of the MR. [12] Also, it is quite interesting that the positive MR remains unsaturated and stabilizes to linear at higher magnetic fields. The fitting for MR at 5 and 300 K, with two different functions, MR ¼ aB þ bB 2 and MR ¼ bB 2 , is shown in Figure S6, Supporting Information.…”