Magnetic and magnetotransport properties of ThCr2Si2-type Ce2O2Bi composed of conducting Bi2- square net and magnetic Ce-O layer

Abstract

ThCr2Si2-type Ce2O2Bi epitaxial thin films were grown by recently developed multilayer solid phase epitaxy. The ionic state of Ce was confirmed to be 3+ by x-ray photoelectron spectroscopy, corresponding to the electronic configuration of [Xe]4f1. Electrical resistivity showed the nonmonotonic temperature dependence with a sharp resistivity maximum, concomitant with a magnetization kink at 10 K, suggesting antiferromagnetic transition. In addition, magnetoresistance showed a large angular-dependent magnetoresistance. These results imply that carrier transport in the Bi2- square net could be influenced by magnetic ordering in the Ce-O layer owing to its unique layered structure [Bi2-/(Ce2O2)2+], particularly in the form of epitaxial thin films.