Ultrafast pseudomagnetic fields from electron-nuclear quantum geometry
Abstract
Recent experiments demonstrate precise control over coherently excited circular phonon modes using high-intensity terahertz lasers, opening new pathways towards dynamical, ultrafast design of magnetism in functional materials. While the phonon Zeeman effect enables a theoretical description of phonon-induced magnetism, it lacks efficient angular momentum transfer from the phonon to the electron sector. In this work, we put forward a coupling mechanism based on electron-nuclear quantum geometry, with the inverse Faraday effect as a limiting case. This effect is rooted in the phase accumulation of the electronic wavefunction under a circular evolution of nuclear coordinates. An excitation pulse then induces a transient level splitting between electronic orbitals that carry angular momentum. First-principle simulations on SrTiO demonstrate that in parts of the Brillouin zone, this splitting between orbitals carrying angular momentum can easily reach 50 meV.
Cite
@article{arxiv.2403.13070,
title = {Ultrafast pseudomagnetic fields from electron-nuclear quantum geometry},
author = {Lennart Klebl and Arne Schobert and Martin Eckstein and Giorgio Sangiovanni and Alexander V. Balatsky and Tim O. Wehling},
journal= {arXiv preprint arXiv:2403.13070},
year = {2025}
}
Comments
6 pages, 3 figures, supplementary information, accepted in PRL