We report on the magnetoelectric dynamics in the linear magnetoelectric antiferromagnet TbPO4 studied by broadband dielectric spectroscopy. For the phase transition into the magnetoelectric antiferromagnetic phase at TN≈2.3 K, a finite magnetic field H induces critical behavior in the quasi-static permittivity ε′. Plotting the corresponding anomaly as function of T/TN(H), we observe the scaling behavior Δε′∝H2, a clear fingerprint of linear magnetoelectric antiferromagnets. Above the phase transition, we find a critical slowing down of the ferroic fluctuations in finite magnetic field. This behaviour can be understood via a magnetic-field-induced relaxational response that resembles the soft-mode behaviour in canonical ferroelectrics and multiferroics.
@article{arxiv.2312.00726,
title = {Magnetic-field-induced critical dynamics in magnetoelectric TbPO$_4$},
author = {Christoph P. Grams and Markus Grüninger and Joachim Hemberger},
journal= {arXiv preprint arXiv:2312.00726},
year = {2024}
}