Emerging Weak Localization Effects on Topological Insulator-Insulating Ferromagnet (Bi₂Se₃-EuS) Interface

الأصل · EN

Thin films of topological insulator Bi₂Se₃ were deposited directly on insulating ferromagnetic EuS. Unusual negative magnetoresistance was observed near the zero field below the Curie temperature (TC), resembling the weak localization effect; whereas the usual positive magnetoresistance was recovered above TC. Such negative magnetoresistance was only observed for Bi₂Se₃ layers thinner than t 4nm, when its top and bottom surfaces are coupled. These results provide evidence for a proximity effect between a topological insulator and an insulating ferromagnet, laying the foundation for future realization of the half-integer quantized anomalous Hall effect in three-dimensional topological insulators.