APS Logo

Manipulation of the Topological Hall Effect with Electric Field in Top-Gated (Bi,Sb)<sub>2</sub>Te<sub>3</sub> on EuIG

ORAL

Abstract

Topological Hall effect (THE), a new member of the “Hall” family, is an electrical transport feature of systems hosting chiral spin textures like skyrmions. Recently, THE has been observed in topological insulator (TI) heterostructures possessing a strong spin-orbit coupling and a broken spatial inversion symmetry when interfaced with a magnetic layer. However, the electrical manipulation of THE has rarely been addressed. In this work, we report a giant THE signal exceeding 3.1 µΩ·cm coexisted with AHE (3.9 µΩ·cm) at 2 K in a 4 nm TI (Bi,Sb)2Te3 (BST) heterostructure with a ferrimagnetic insulator europium iron garnet. Dependences of temperature, magnetic field angle, and gate bias were investigated in a four-terminal Hall bar device implemented with a top electrical gate. The THE diminished with increasing temperatures and disappeared above 75 K. Furthermore, the observation of THE at zero fields suggested a stable skyrmion phase without the support of an external magnetic field. The magnitude of THE remained nearly the same up to 70° as the magnetic field gradually tilted away from the surface normal (0°) to the in-plane direction (90°). Most importantly, the sign of THE was switched from negative to positive as carriers in BST were altered from electrons to holes via the gate bias, consistent with the prediction of a skyrmion-driven THE. Our demonstration of electrical manipulation of THE in TI-based heterostructures has important technological implications for ultralow power skyrmion-based spintronics.

–

Presenters

  • Ko-Hsuan Chen

    Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan

Authors

  • Jyun-Fong Wong

    Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan

  • Ko-Hsuan Chen

    Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan

  • Jui-Min Chia

    Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan

  • Zih-Ping Huang

    Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan

  • Sheng-Xin Wang

    Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan

  • Pei-Tze Chen

    Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan

  • Lawrence Boyu Young

    National Taiwan University, Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan

  • Yen-Hsun Glen Lin

    National Taiwan University, Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan

  • Shang-Fan Lee

    Institute of Physics, Academia Sinica, Taipei 11529, Taiwan

  • Chung-Yu Mou

    Center for Quantum Technology and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Natl Tsing Hua University

  • Minghwei Hong

    National Taiwan University, Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan

  • Jueinai Kwo

    National Tsing Hua University, Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan