Nickel-induced metal-insulator transition in the small A cation manganites Ln{sub 0.5}Ca{sub 0.5}MnO{sub 3}

Journal Article · Tue Jul 01 04:00:00 EDT 1997 · Materials Research Bulletin

DOI:https://doi.org/10.1016/S0025-5408(97)00067-6· OSTI ID:514733

Maignan, A; Damay, F; Martin, C; Raveau, B ^[1]

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1. Univ. de Caen (France). Lab. CRISMAT

The study of the manganites Ln{sub 0.5}Ca{sub 0.5}Mn{sub 1{minus}x}Ni{sub x}O{sub 3} (Ln = Pr, Nd, Sm) shows that the introduction of nickel on the Mn site provokes the disappearance of charge ordering (CO). But most important, it is demonstrated for the first time that doping with nickel induces a metal-insulator transition for Ln = Pr or Nd, in spite of the small size of the interpolated cations. All the compounds of these series exhibit colossal magnetoresistance (CMR) properties with resistance ratios (RR) ranging from 5.10{sup 3} at 75 K to 10{sup 8} at 60 K under 7 T, whereas the undoped phases either are not magnetoresistant (Ln = Pr, Sm) or exhibit much smaller RR (20 at 100 K for Ln = Nd). The magnetotransport properties of these Ni-doped manganites are compared to those of Cr- and Co-doped phases and their evolution is discussed, taking into consideration two antagonist factors: the average size of the interpolated cations and the size mismatch between Ln{sup 3+} and Ca{sup 2+}.

• OSTI ID: 514733
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 7 Vol. 32; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM OXIDES
FERROMAGNETIC MATERIALS
MAGNETORESISTANCE
MANGANESE OXIDES
METALLURGICAL EFFECTS
NEODYMIUM OXIDES
NICKEL
ORDER PARAMETERS
PARAMAGNETISM
PHASE TRANSFORMATIONS
PRASEODYMIUM OXIDES
SAMARIUM OXIDES