Effects of the relative proportion of ferromagnetic and charge-ordered phases on the metal–insulator transition temperature in La0.5Ca0.5Mn1−xGexO3
2000; American Institute of Physics; Volume: 88; Issue: 12 Linguagem: Inglês
10.1063/1.1327600
ISSN1520-8850
AutoresRun-Wei Li, Jirong Sun, Zhihong Wang, Shao-ying Zhang, Ning Tang, Baogen Shen,
Tópico(s)Rare-earth and actinide compounds
ResumoMagnetic and transport properties of rare-earth manganites La0.5Ca0.5Mn1−xGexO3 with 0⩽x⩽0.1 have been investigated systematically. Doping Ge at Mn sites increases the metal–insulator transition temperature (TP) from 124 to 210 K with increasing x from 0 to 0.08. The introduction of Ge severely destroys the charge-ordered state and hardly affects the ferromagnetic ordering. For low-doped samples, TP is also increased dramatically by the magnetic field, especially in the field-cooled mode. Magnetic analysis suggests the coexistence of the charge-ordered antiferromagnetic phase and the ferromagnetic phase. We propose that the proportion of the ferromagnetic phase and the charge-ordered phase can affect TP in phase-separated compounds. The phase diagram of La0.5Ca0.5Mn1−xGexO3 with 0⩽x⩽0.1 is presented.
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