Phase Separation and Transport Behaviors in La0.7-x DyxSr0.3MnO3 System
CAI Zhi-rang1，LIU Ning1, 2, TONG Wei2，XU Su-jun2，ZHANG Yu-heng2
1. CMR Materials Research Laboratory, Suzhou College, Suzhou 234000, China 2. Structure Research Laboratory, University of Science and Technology of China, Hefei 230026，China
Abstract：The influence of Dy doping (0.00≤x≤0.30) on magnetic and electric properties of La0.7Sr0.3MnO3 was studied by measuring M-T curves, M-H curves, ESR curves, ρ-T curves and MR-T curves of the samples. The experimental results indicate that all samples undergo the transition from paramagnetism to ferromagnetism at TC. When T＜TC, the doped samples enter the cluster-spin glass state, and the antiferromagnetism is exhibited at lower temperature. For the samples x=0.2 , the phase separation occurs at thetemperature far above TC，the variation in magnetic structure caused by Dy doping leads to colossal magnetoresistance.
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