Magnetic heterostructures of topological insulators for gigantic magnetoresistance and axion insulator

ORAL

Abstract

The quantum anomalous Hall (QAH) effect observed in magnetic topological insulators (TIs) draws much attention to possible application for low-energy consumption electronic devices and a platform for the axion electrodynamics as fundamental physics. Here, we designed a magnetic TI with a trilayer structure in which a nonmagnetic layer of (Bi, Sb)2Te3 is sandwiched by a soft-ferromagnetic Cr-doped (Bi, Sb)2Te3 and a hard-ferromagnetic V-doped (Bi, Sb)2Te3. Accompanied by the QAH effect, we observed wide zero Hall conductivity plateaus via the magnetization reversal. Two-terminal resistance during the zero-Hall plateau state reaches as high as giga-ohms, leading to gigantic magnetoresistance upon the transition from the QAH state (~ 26 kilo-ohms). Furthermore, the high resistance state is a new topological phase termed as axion insulator state, promising realization of topological magnetoelectric effect.

*This research was supported by JST CREST (no. JPMJCR16F1) and JSPS through a research fellowship for young scientists (no. 17J03179).

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Presenters

  • Masataka Mogi

    • Univ of Tokyo
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • Applied Physics, University of Tokyo

Authors

  • Masataka Mogi

    • Univ of Tokyo
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • Applied Physics, University of Tokyo

  • Minoru Kawamura

    • RIKEN Center for Emergent Matter Science

  • Atsushi Tsukazaki

    • Institute for Materials Reaserch, Tohoku University
    • Tohoku Univ
    • Institute for Materials Research, Tohoku University
    • IMR, Tohoku University
    • Institute for Materials Research
    • Tohoku University
    • Tohoku Univ.

  • Ryutaro Yoshimi

    • RIKEN
    • RIKEN Center for Emergent Matter Science

  • Kei Takahashi

    • RIKEN
    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN Center for Emergent Matter Science
    • CEMS, RIKEN
    • Center for Emergent Matter Science (CEMS), RIKEN

  • Masashi Kawasaki

    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Univ of Tokyo
    • The University of Tokyo
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo
    • Applied Physics, University of Tokyo
    • Department of Applied Physics, The University of Tokyo
    • Department of Applied Physics, University of Tokyo

  • Yoshinori Tokura

    • RIKEN Center for Emergent Matter Science (CEMS)
    • CEMS, RIKEN
    • RIKEN
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • RIKEN Center for Emergent Matter Science
    • Center for Emergent Matter Science (CEMS), RIKEN
    • Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo