Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Anisotropic and thermally activated resistive behavior in Nd sub 1. 85 Ce sub 0. 15 CuO sub 4 minus. delta

Journal Article · · Physical Review, B: Condensed Matter; (USA)
;  [1]
  1. NTT Opto-Electronics Laboratoires, Nippon Telegraph and Telephone Corporation, 162 Tokai-mura, Ibaraki-ken 319-11, (Japan)

An anisotropic-field-induced resistive transition has been measured for highly {ital c}-axis-oriented Nd{sub 1.85}Ce{sub 0.15}CuO{sub 4{minus}{delta}} thin films as a function of a magnetic field {bold H} parallel and perpendicular to the {ital c} axis. It is found that the observed resistivity {rho} below {ital T}{sub {ital c}} scales as {rho}({ital T})={rho}{sub 0} exp{l brace}{minus}{ital U}({ital H})(1{minus}{ital T}/{ital T}{sub {ital c}}({ital H})){sup {ital n}}/{ital k}{sub {ital B}T}{r brace} with {ital n}=2 for {bold H}{perpendicular}{bold c} and {ital n}=3 for {bold H}{parallel}{bold c}. This resistive behavior is explained by thermally activated flux motion based on a depinning model for flux lines in a quasi-two-dimensional superconductor. Numerical fitting leads to an estimation of the upper critical field, which results in a straight {ital H}-{ital T} phase boundary in quite a wide range below {ital T}{sub {ital c}} with upward deviation at lower temperatures.

OSTI ID:
6883808
Journal Information:
Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 41:13; ISSN 0163-1829; ISSN PRBMD
Country of Publication:
United States
Language:
English