Dynamic axion field in the magnetoelectric antiferromagnet chromia
Junlei Wang, Chao Lei, Allan H. MacDonald and Christian Binek
Received Date: 11th January 19
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’s magnetoelectric response couples strongly to its low-energy quantum and thermal spin fluctuations.
Read in full at arXiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.