Anomalous magnetoresistance in topological insulator Bi₂Te₃

Abstract

Abstract

A proximity-induced superconductivity is used in a single crystal flake Bi₂Te₃ topological insulator to probe the behavior of magnetoresistance around the local superconducting critical fields. The magnetoresistance in Bi₂Te₃ and GaAs materials with superconducting contacts are studied and compared. A contradictory behavior in both of the systems is observed (A positive resistance correction was observed in GaAs, whereas a negative resistance correction was observed in Bi₂Te₃). For Bi₂Te₃, periodic oscillations are observed in the dR/d|B| verses B plots. These periodic oscillations originate from a coexistence of proximity-induced superconductivity with a normal linear region created either by temperature or applied magnetic field. At high magnetic fields (> 2T) and low temperatures (1.5K), Shubnikov de Hass oscillations are also observed. Copyright © 2016 VBRI Press

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