Effect of tolerance factor and local distortion on magnetic properties of the perovskite manganites

Journal Article · Sun Aug 01 00:00:00 EDT 1999 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.124624· OSTI ID:362660

Zhou, J P; McDevitt, J T ^[1]; Zhou, J S; Yin, H Q; Goodenough, J B ^[2]; Gim, Y; Jia, Q X ^[3]

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1. Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712 (United States)
2. Center for Materials Science and Engineering, University of Texas at Austin, Austin, Texas 78712 (United States)
3. Superconductivity Technology Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

The substitutions of rare earths for La on the magnetic properties of the perovskites La{sub 0.7{minus}x}R{sub x}A{sub 0.3}MnO{sub 3} (0{lt}x{lt}0.7), R=Pr or Gd and A=Ca, Sr, or Ba have shown that small substitution of Pr slightly increases the coercive field H{sub c} and magnetization {ital M}, and strongly improves the magnetoresistance (MR) while lowering T{sub c}. On the other hand, the substitution of Gd lowers H{sub c}, {ital M} and T{sub c}, however, increases MR of the system La{sub 0.7{minus}x}Gd{sub x}Sr{sub 0.3}MnO{sub 3} at temperature {lt}T{sub c}. Large differences in the A-site ionic radii r{sub A} of the AMnO{sub 3} perovskites proved detrimental. The optimal composition has been discussed for the half-metallic ferromagnet of a spin-switch device based on the manganese oxides. {copyright} {ital 1999 American Institute of Physics.}

• OSTI ID: 362660
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 8 Vol. 75; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
CALCIUM OXIDES
CHEMICAL COMPOSITION
COERCIVE FORCE
CURIE POINT
FERROMAGNETIC MATERIALS
GADOLINIUM OXIDES
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MAGNETIZATION
MAGNETORESISTANCE
MANGANESE ORES
PEROVSKITES
PRASEODYMIUM OXIDES
RARE EARTH COMPOUNDS
STRONTIUM OXIDES
TEMPERATURE DEPENDENCE