Establishment and Melting of Charge Ordering in La0.3Ca0.7Mn1-xWxO3 System
CAI Zhi-rang1,GUO Huan-yin1,LIU Ning1，2,ZHANG Yu-heng2
1. Materials Research Laboratory, Suzhou College，Suzhou 234000, China 2. Structure Research Laboratory, University of Science and Technology of China, Hefei 230026, China
Abstract：Polycrystalline samples of La0.3Ca0.7Mn1-xWxO3 (0.00≤x≤0.15) were prepared by conventional solid-state reaction method. The influence of W doping at Mn site on the magnetic transition of La0.3Ca0.7Mn1-xWxO3 system was studied by the measurements of magnetization-temperature (M-T) curves，magnetization-magnetic intensity(M-H) curves, and ESR spectra. The results show that, with the increase in W doping amount, the magnetic transition of the system exhibits a complicated charge process, when the doping amount is 0.00≤x≤0.08, the charge-ordering(CO) phase exists in the system, AFM/CO states coexist below the transition temperature, and the charge-ordering temperature(Tco) goes up with the increase in W doping content; when x≥0.12, the charge ordering (CO) state of the system weakens and melts, and paramagnetism-ferromagnetism (PM-FM) transition exists at extremely low temperature.
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