Quantum Hall Physics in Magnetic Topological Insulators

Abstract

Magnetic topological insulator, where spontaneous magnetization is introduced by magnetic doping, realizes quantum anomalous Hall effect (QAHE). The chiral edge state (CES) at the edge of QAHE is a promising candidate for a dissipationless electronic channel under zero magnetic field. The realization temperature of QAHE was, however, extremely low below one hundred mK. To overcome this limitation, we fabricated a magnetic modulation-doped topological insulator and realized QHE and QAHE above 2 K. We utilized the high-temperature QAHE to prove and manipulate CES at the magnetic domain wall employing magnetic force microscope.