Home > Agenda Scientifique

27 February 2020: One event

séminaire

  • Novel magnetoelectric effect in gyrotropic crystals and current induced magnetization switching

    Thursday 27 February 11:00-12:00 - Wen-Yu He - Hong Kong University of Science and Technology

    Novel magnetoelectric effect in gyrotropic crystals and current induced magnetization switching

    Résumé : In noncentrosymmetric metals, a current induced net magnetization is known as the magnetoelectric effect (or Edelstein effect). In past years, studies of the current driven magnetization mainly focused on polar crystals with Rashba spin-orbit coupling, where the magnetization is perpendicular to both the polar axis and current direction. Recently, many noncentrosymmetric materials emerged with various types of spin-orbit coupling and nonzero Berry curvature, but their magnetoelectric response has not been studied.
    I will present the general theory for the current induced magnetization and show how the crystal symmetry determines the magnetoelectric response. In crystals with chiral lattice symmetry, we will show that applying current can induce magnetization parallel to the current direction, which resembles a solenoid. In quasi-2D materials, we will show how the in-plane current can control out of plane magnetization and explain the recent observed DC current induced magnetization switching in twisted bilayer graphene. We further extend our theory to the superconductivity region and show that superconductors with gyrotropic point group symmetry can have novel magnetization driven by supercurrent, which does not have energy dissipation.

    Lieu : Salle 208a, bat 510, LPS

    En savoir plus : Novel magnetoelectric effect in gyrotropic crystals and current induced magnetization switching