Magnetic Properties and Transport Behaviors in Double Doped La0.67+1.33xSr0.33-1.33xMn1-xMgxO3 System
CAI Zhi-rang1，TONG Wei2，ZHANG Meng2，ZHANG Bei2，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：The M-T curves, M-H curves, ESR curves, infrared spectrum, Raman spectrum, ρ-T curves and MR-T curves of La0.67+1.33xSr0.33-1.33xMn1-xMgxO3(0.00≤x≤0.25) were studied. The experiment pointed out that all samples exhibit a paramagnetic-ferromagnetic(PM-FM) transition associated with metallic-insulating(MI) transition in the low doping region, which does not occur in the heavy doping zone. The authors suggest that this behavior is attributed to the difference between the Jahn-Teller distortion of the Mn3+ ion neighboring Mg2+ and that of the Mn3+ ion non-neighboring Mg2+, which is confirmed by the IR and Raman spectra. The anomalous transport behavior is dominated by the differerent Jahn-Teller distortion.
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