Quadruple perovskite oxide LaCu3Co2Re2O12: A ferrimagnetic half metal with nearly 100% B-site degree of order
Zhehong Liu, Qian Sun, Xubin Ye, Xiao Wang, Long Zhou, Xudong Shen, Kai Chen, Lucie Nataf, F. Baudelet, Stefano Agrestini, Chien‐Te Chen, Hong‐Ji Lin, Hari Babu Vasili, Manuel Valvidares, Zhiwei Hu, Yi‐feng Yang, Youwen Long
Abstract
An A- and B-site ordered quadruple perovskite oxide LaCu3Co2Re2O12 was synthesized at 9 GPa and 1323 K. The compound possesses a Pn-3 space group, where both A and B sites are orderly occupied by different cations with a nearly 100% degree of order. Bond valence sum calculations and x-ray absorption spectroscopy confirm the charge distribution to be LaCu2+3Co2+2Re5.5+2O12. A ferrimagnetic phase transition is found to occur around 150 K due to the Cu2+(↑)-Co2+(↑)-Re5.5+(↓) spin coupling found by x-ray magnetic circular dichroism at Cu-, Co-, and Re-L2,3 edges. The magnetoresistance effects as well as the first-principle calculations indicate the half-metallic nature for LaCu3Co2Re2O12 with a wider energy gap at the up-spin channel and a conducting band at the down-spin channel.