摘要
Polycrystalline samples of La0.4Cao.6Mn1-xCrxO3 (x = 0.00, 0.02, 0.04, 0.06) were prepared by the solid state reaction method. The influence of Cr3+ substitution for Mn3+ on the magnetic property and charge ordering phase of La0.4Ca0.6MnO3 was studied through the measurements of X-ray diffraction (XRD), magnetization-temperature (M-T) curves and electron spin resonance (ESR) spectra. The experimental results indicate that the mother's body of La0.4Ca0.6MnO3 has very complicated magnetic structure, exhibits charge ordering phase at 258 K, and shows long-range strongly correlated charge ordering-antiferromagnetism (CO-AFM) phase from 175 to 50 K. Spin glass state appears when the temperature decreases to about 41 K. When the Cr substitution amount is x = 0.06, the charge ordering phase of the mother's body is de-stroyed, because the Cr3+ substitution for Mn3+ destroys the spin order of CE-type antiferromagnetism, and thus leads to the melting of charge ordering. It is verified experimentally that the strong coupling between charge order and spin order exists in the charge order system of CE-type antiferromagnetism.
Polycrystalline samples of La0.4Cao.6Mn1-xCrxO3 (x = 0.00, 0.02, 0.04, 0.06) were prepared by the solid state reaction method. The influence of Cr3+ substitution for Mn3+ on the magnetic property and charge ordering phase of La0.4Ca0.6MnO3 was studied through the measurements of X-ray diffraction (XRD), magnetization-temperature (M-T) curves and electron spin resonance (ESR) spectra. The experimental results indicate that the mother's body of La0.4Ca0.6MnO3 has very complicated magnetic structure, exhibits charge ordering phase at 258 K, and shows long-range strongly correlated charge ordering-antiferromagnetism (CO-AFM) phase from 175 to 50 K. Spin glass state appears when the temperature decreases to about 41 K. When the Cr substitution amount is x = 0.06, the charge ordering phase of the mother's body is de-stroyed, because the Cr3+ substitution for Mn3+ destroys the spin order of CE-type antiferromagnetism, and thus leads to the melting of charge ordering. It is verified experimentally that the strong coupling between charge order and spin order exists in the charge order system of CE-type antiferromagnetism.
基金
supported by the Key Program of the National Natural Science Foundation of China (No.19934003)
the Key Program of Natural Science Research of Anhui Education Department (No.KJ2011A259
KJ2008A34ZC)
the Natural Science Research Programs of Anhui Education Department, China (No.KJ2010B229
No.KJ2010B228
No.KJ2009B281Z)