Dynamic multiferroicity of a ferroelectric quantum critical point

ORAL

Abstract

Dynamical multiferroicity, where fluctuations of electric dipoles lead to magnetisation, is an example of where two coexisting orders are impossible to disentangle [1]. We calculate the magnetic susceptibility near the ferroelectric quantum critical point (FE QCP) and find a region with enhanced magnetic signatures that appears near the FE QCP, and is controlled by the tuning parameter of the ferroelectric phase. We thus suggest that any ferroelectric quantum critical point may be an inherent multiferroic quantum critical point. The effect is small but observable, and we suggest the quantum paraelectric strontium titanate as a candidate material where the magnitude of the induced magnetic moments can be ~5 x 107 µB per unit cell
near the FE QCP [2].

[1] D. M. Juraschek et al., PhysRevMat.1.014401 (2017).
[2] K. Dunnett et al., arXiv:1808.05509 (2018).

*VILLUM FONDEN via the Centre of Excellence for Dirac Materials (Grant No. 11744)
The Knut and Alice Wallenberg Foundation (2013.0096)

Presenters

  • Kirsty Dunnett

    • Nordic Institute for Theoretical Physics, Stockholm
    • Condensed Matter, Nordita, Stockholm, Sweeden

Authors

  • Kirsty Dunnett

    • Nordic Institute for Theoretical Physics, Stockholm
    • Condensed Matter, Nordita, Stockholm, Sweeden
  • Jian-Xin Zhu

    • Theoretical Division, Los Alamos National Laboratory
    • Los Alamos National Laboratory
    • Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • T4-PHYS OF CONDENSED MATTER & COMPLEX SYS, Los Alamos National Laboratory, Los aAlamos, USA
    • CINT, Los Alamos National Laboratory
    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory
    • Los Alamos National Laboratory,
  • Nicola Spaldin

    • ETH Zurich
    • Materials Theory, ETH Zürich
    • Department of Materials, ETH Zürich
  • Vladimir Juricic

    • NORDITA, Nordic Institute for Theoretical Physics, Stockholm University and KTH, Stockholm, Sweden
    • NORDITA, the Nordic Institute for Theoretical Physics, Stockholm University and KTH, Stockholm, Sweden
    • Nordic Institute for Theoretical Physics, Stockholm
  • Alexander Balatsky

    • Nordita
    • Los Alamos National Laboratory
    • Nordic Institute for Theoretical Physics, Stockholm
    • Institute for Materials Science, Los Alamos National Laboratory
    • NORDITA
    • Nordic Institute for Theoretical Physics
    • Los Alamos National Laboratory, Institute for Materials Science
    • Institute for Material Science, Los Alamos National Laboratory
    • Department of Physics, University of Connecticut, Storrs, CT 06269, USA