Dynamic axion field in the magnetoelectric antiferromagnet chromia
Mesoscale and Nanoscale Physics
2019-01-25 v1 Materials Science
Abstract
Chromia is a magnetoelectric insulator whose bulk magnetoelectric susceptibility contains a non-zero pseudoscalar component, like that present in magnetized topological insulators. We reveal the dynamic axion field of chromia by measuring the temperature dependence of its non-linear magnetoelectric response using a lock-in technique with an AC electric field stimulus. The electric field dependence, magnetic field dependence, and temperature behavior of the second harmonic lock-in signal are all in agreement with theoretical expectations. Our results demonstrate that chromia magnetoelectric response couples strongly to its low-energy quantum and thermal spin fluctuations.
Keywords
Cite
@article{arxiv.1901.08536,
title = {Dynamic axion field in the magnetoelectric antiferromagnet chromia},
author = {Junlei Wang and Chao Lei and Allan H Macdonald and Christian Binek},
journal= {arXiv preprint arXiv:1901.08536},
year = {2019}
}