The recent realization of epitaxial SrCoO3 thin films has triggered a renewed interest in their electronic, magnetic, and ionic properties. Here we uncover several unusual magneto-transport properties of this compound, suggesting that it hosts persistent spin fluctuation down to low temperatures. We achieve the metallic SrCoO3 with record-low resistivity from insulating SrCoO2.5 by the ionic liquid gating. We find a linear relationship between the anomalous Hall resistivity and the longitudinal resistivity, which cannot be accounted for by the conventional mechanisms. We theoretically propose that the impurity induced chiral spin fluctuation gives rise to such a dependence. The existence of spin fluctuation manifests itself as negatively enhanced magneto-resistance of SrCoO3 when the temperature approaches zero. Our study brings further insight into the unique spin state of SrCoO3 and unveils a novel skew scattering mechanism for the anomalous Hall effect.
@article{arxiv.1807.10877,
title = {Anomalous Hall Effect and Spin Fluctuations in Ionic Liquid Gated SrCoO$_3$ Thin Films},
author = {Ding Zhang and Hiroaki Ishizuka and Nianpeng Lu and Yujia Wang and Naoto Nagaosa and Pu Yu and Qi-Kun Xue},
journal= {arXiv preprint arXiv:1807.10877},
year = {2018}
}