Magnetoresistivity of thin films of the electron-doped high-{ital T}{sub {ital c}} superconductor Nd{sub 1.85}Ce{sub 0.15}CuO{sub 4{plus_minus}{delta}}

Journal Article · Thu Aug 01 00:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.54.3610· OSTI ID:288794

Herrmann, J; de Andrade, M C; Almasan, C C; Dickey, R P; Maple, M B ^[1]; Jiang, W; Mao, S N; Greene, R L ^[2]

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1. Department of Physics and Institute for Pure and Applied Physical Sciences, University of California, San Diego, La Jolla, California 92093-0360 (United States)
2. Center for Superconductivity Research, University of Maryland, College Park, Maryland 20742 (United States)

We report measurements of the magnetoresistance of Nd{sub 1.85}Ce{sub 0.15}CuO{sub 4{plus_minus}{delta}} epitaxial thin films with varying oxygen content in magnetic fields {ital H} applied parallel ({ital H}{parallel}{ital c}) and perpendicular ({ital H}{perpendicular}{ital c}) to the tetragonal {ital c} axis. We have observed critical scaling of the electrical resistivity that is consistent with a vortex-glass transition for a film with an optimum superconducting transition temperature {ital T}{sub {ital c}} of {approx_equal}22 K and {ital H}{parallel}{ital c}. The values of the zero-temperature upper critical field {ital H}{sub {ital c}{sub 2}}(0)=80 kOe and the in-plane zero-temperature coherence length {xi}{sub {ital ab}}(0)=64 A were obtained from an analysis of the fluctuation conductivity. For an overoxygenated film with {ital T}{sub {ital c}}{approx_equal}10 K, an anomaly develops with increasing field for {ital H}{parallel}{ital c} and {ital T}{approx_lt}2 K that is characterized by a minimum in the temperature dependence of the resistivity followed by a second resistive transition at a lower temperature, which is nearly independent of {ital H}. This behavior is similar to that previously observed in Nd{sub 2{minus}{ital x}}Ce{sub {ital x}}CuO{sub 4{minus}{delta}} single crystals and may be associated with the magnetic ordering of the Nd{sup 3+} ions. {copyright} {ital 1996 The American Physical Society.}

• DOE Contract Number: FG03-86ER45230
• OSTI ID: 288794
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 5 Vol. 54; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM OXIDES
COHERENCE LENGTH
CRITICAL FIELD
CUPRATES
ELECTRIC CONDUCTIVITY
EPITAXY
FLUCTUATIONS
HIGH-TC SUPERCONDUCTORS
MAGNETIC FLUX
MAGNETORESISTANCE
NEODYMIUM OXIDES
PHASE STUDIES
STOICHIOMETRY
SUPERCONDUCTING FILMS
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
THIN FILMS
TYPE-II SUPERCONDUCTORS