We report the observation of anomalous Hall resistivity in single crystals of EuAl4, a centrosymmetric tetragonal compound, which exhibits coexisting antiferromagnetic (AFM) and charge-density-wave (CDW) orders with onset at TN∼15.6 K and TCDW∼140 K, respectively. In the AFM state, when the magnetic field is applied along the c-axis direction, EuAl4 undergoes a series of metamagnetic transitions. Within this field range, we observe a clear hump-like anomaly in the Hall resistivity, representing part of the anomalous Hall resistivity. By considering different scenarios, we conclude that such a hump-like feature is most likely a manifestation of the topological Hall effect, normally occurring in noncentrosymmetric materials known to host nontrivial topological spin textures. In view of this, EuAl4 would represent a rare case where the topological Hall effect not only arises in a centrosymmetric structure, but it also coexists with CDW order.
@article{arxiv.2012.06088,
title = {Anomalous Hall resistivity and possible topological Hall effect in the EuAl$_4$ antiferromagnet},
author = {T. Shang and Y. Xu and D. J. Gawryluk and J. Z. Ma and T. Shiroka and M. Shi and E. Pomjakushina},
journal= {arXiv preprint arXiv:2012.06088},
year = {2021}
}