Abnormal colossal electroresistance in Ru-doped La0.225Pr0.4Ca0.375MnO3

作者：Che P H; Yan Z B^*; Liu M F; Wang Y L; Zhou X H; Liu J M

来源：Journal of Applied Physics, 2015, 117(17): 17C722.

DOI：10.1063/1.4913941

We investigate the magnetic and transport properties of polycrystalline bulk La0.225Pr0.4Ca0.375 Mn1-xRuxO3 (x <= 0.15). With a slight Ru substitution of Mn, the Curie temperature of ferromagnetic transition is raised, the thermal hysteresis of resistivity is suppressed, and two metal-insulator transitions (MITs) coming from different mechanisms are observed. Furthermore, we observe that the resistivity of La0.225Pr0.4Ca0.375Mn1-xRuxO3 (0.01 <= x <= 0.1) increases abnormally with external electric field, and external magnetic field can suppress such abnormal electroresistance. These results suggest that the slight doping of Ru greatly suppresses the antiferromagnetic charge-ordered insulating (AFM/COI) phase. The Mn3+-Ru4+ ferromagnetic super-exchange and possible Ru4+-Ru4+ AFM interaction are implied to explain the observed behaviors.

• 出版日期2015-5-7
• 单位南京大学