Magnetism of Fe, Ni, and Zn in Nd{sub 1.85}Ce{sub 0.15}CuO{sub 4}: Comparison of experiment and theory

Journal Article · Tue Aug 01 00:00:00 EDT 1995 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.52.3742· OSTI ID:83947

Jayaram, B ^[1]; Chen, H ^[2]; Callaway, J ^[3]

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1. Materials Science Program, Department of Physics, University of Nebraska at Omaha, Omaha, Nebraska 68182-0266 (United States)
2. Chemical Research and Engineering Division, Cray Research, Inc., Eagan, Minnesota 55121 (United States)
3. Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803-4001 (United States)

We have studied the magnetic and superconducting properties of Fe- , Ni- , and Zn-substituted Nd{sub 1.85}Ce{sub 0.15}CuO{sub 4} bulk materials. The normal-state magnetic susceptibility of all samples is found to follow the Curie-Weiss law between 50 and 300 K. The magnitude of local moments deduced for Fe and Ni are 2.2{mu}{sub {ital B}} and 2{mu}{sub {ital B}}, respectively. The observed moment on Ni is attributed to Ni in a 3+ valency state. A magnetic moment of 0.8{mu}{sub {ital B}} is obtained in Zn-substituted samples. This is ascribed to the localized Cu{sup 2+} spins. The {ital T}{sub {ital c}} vs 3{ital d} ion concentration ({ital x}) curves indicate that Ni inhibits the {ital T}{sub {ital c}} of this system at an anomalously higher rate. In an effort to understand the correlation between the magnitude of the magnetic moment on the 3{ital d} ion and its role in the suppression of superconductivity, we have performed density-functional cluster calculations under local-spin-density approximations. The calculations support the following inferences drawn from the experiments: (i) Ni is in a 3+ state, (ii) the moment of 0.8{mu}{sub {ital B}} observed in Zn-substituted samples is due to localized Cu{sup 2+} spins, and (iii) Zn induces a moment of almost the same magnitude in both the electron-doped and the hole-doped La{sub 1.85}Sr{sub 0.15}CuO{sub 4} systems. We have also attempted to explain qualitatively the observed {ital T}{sub {ital c}} vs {ital x} behavior in the above systems using the effective single-band {ital t}-{ital J} model.

• Research Organization: Purdue Univ., West Lafayette, IN (United States)
• DOE Contract Number: FG02-90ER45427
• OSTI ID: 83947
• Journal Information: Physical Review, B: Condensed Matter, Vol. 52, Issue 5; Other Information: PBD: 1 Aug 1995
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CUPRATES
MAGNETIC PROPERTIES
ELECTRIC CONDUCTIVITY
CERIUM OXIDES
NEODYMIUM OXIDES
HIGH-TC SUPERCONDUCTORS
TRANSITION TEMPERATURE
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K
MAGNETIZATION
IRON ADDITIONS
NICKEL ADDITIONS
ZINC ADDITIONS
CURIE-WEISS LAW