摘要
M-T curves, ρ-T curves and MR-T curves of La0.67Sr0.33Mn1-xCrxO3(0.00≤ x ≤0.30) were studied. Experimental results indicate that the substitution of Cr on Mn sites is impotent in driving Tc, but with an increase of Cr content, there appear two peaks in resistivity and MR response, thus the temperature range of CMR response is significantly broadened. The extraordinary transport behavior and the abnormal CMR effect could be the results of coexistence and competition of Mn^3 + -O-Mn^4 + and Mn^3+ -O-Cr^3 + channels.
M-T curves, ρ-T curves and MR-T curves of La0.67Sr0.33Mn1-xCrxO3(0.00≤ x ≤0.30) were studied. Experimental results indicate that the substitution of Cr on Mn sites is impotent in driving Tc, but with an increase of Cr content, there appear two peaks in resistivity and MR response, thus the temperature range of CMR response is significantly broadened. The extraordinary transport behavior and the abnormal CMR effect could be the results of coexistence and competition of Mn^3 + -O-Mn^4 + and Mn^3+ -O-Cr^3 + channels.
基金
ProjectsupportedbytheNationalNaturalScienceFoundationofChina(19934003),theStateKeyProjectofFundamentalResearchofChina(001CB610604)andtheNaturalScienceFoundationoftheAnhuiHigherEducationInstitutionsofChina(2006KJ266B)