Anomalous magnetoresistance in topological insulator Bi2Te3

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