The spin texture in a SrTiO<sub>3</sub>(111) two-dimensional electron gas

ORAL

Abstract

We report the observation of a bilinear magnetoelectric resistance (BMER) signal in the d-orbital two-dimensional electron gas (2DEG) at the SrTiO3 (STO) (111) surface, demonstrating a spin-splitting. We show that our BMER measurements reveal a three-fold symmetric out-of-plane spin component that breaks the six-fold symmetry of the 2DEG subband dispersion, and an in-plane spin component locked perpendicularly to the momentum. By performing tight-binding supercell calculations based on the relativistic density functional theory of the STO bulk band structure, we find that this 3D spin texture is fully described by the effects of confinement of the STO t2g conduction band in the (111) plane. We also show that the BMER can be substantially tuned through oxygen vacancy doping, electrostatic gating and temperature variation. Our findings highlight the untapped potential of SrTiO3 (111) based 2DEGs as a playground for spintronic applications.

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Presenters

  • Pan He

    • Department of Electrical and Computer Engineering, National University of Singapore

Authors

  • Pan He

    • Department of Electrical and Computer Engineering, National University of Singapore

  • Siobhan McKeown Walker

    • Department of Quantum Matter Physics, University of Geneva

  • Shulei Zhang

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory, Lemont, Illinois, USA
    • Materials Science Division, Argonne National Laboratory

  • F. Y. Bruno

    • Department of Quantum Matter Physics, University of Geneva

  • M. S. Bahramy

    • Quantum-Phase Electronics Center, The University of Tokyo

  • Jongmin Lee

    • Department of Electrical and Computer Engineering, National University of Singapore

  • Rajagopalan Ramaswamy

    • Department of Electrical and Computer Engineering, National University of Singapore

  • Kaiming Cai

    • Department of Electrical and Computer Engineering, National University of Singapore

  • Olle Heinonen

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory, Lemont, Illinois, USA

  • Giovanni Vignale

    • University of Missouri
    • Department of Physics and Astronomy, University of Missouri
    • University of Missouri (USA) & Yale-NUS College (Singapore)

  • Felix Baumberger

    • Department of Quantum Matter Physics, University of Geneva

  • Hyunsoo Yang

    • Department of Electrical and Computer Engineering, and NUSNNI-NanoCore, National University of Singapore
    • Department of Electrical and Computer Engineering, National University of Singapore