Investigation of anomalous magnetoresistance in topological insulator Bi_2Te_3 at the onset of superconductivity in indium contacts

摘要

Presented here is evidence that suggests induced superconductivity in topological insulator Bi_2Te_3 occurring at its interface with indium (In) contacts. Thin Bi_2Te_3 films of several thicknesses were grown by molecular beam epitaxy and were studied by magnetotransport measurements using In as contacts. Magnetotransport measurements at temperatures below the superconducting transition of In reveal an anomalous abrupt drop in resistance of the Bi_2Te_3 samples suggesting the formation of a superconducting region at the In/Bi_2Te_3 interface induced by the In contacts.