Resistive transition, magnetoresistance, and anisotropy in La sub 2 minus x Sr sub x CuO sub 4 single-crystal thin films (JP)

Journal Article · Mon Jul 01 00:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.44.249· OSTI ID:5662980

Suzuki, M; Hikita, M ^[1]

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1. NTT Applied Electronics Laboratories, NTT Ibaraki Research and Development Center, Nippon Telegraph and Telephone Corporation, 162 Tokai, Ibaraki 319-11, (Japan)

The temperature dependence of the resistivity {rho}({ital T}) in the vicinity of the superconducting transition temperature {ital T}{sub {ital c}} has been measured for thin-film single crystals of La{sub 2{minus}{ital x}}Sr{sub {ital x}}CuO{sub 4} as a function of an applied magnetic field, both parallel and perpendicular to the {ital c} axis. The resistive transition exhibits characteristic behavior, depending on the Sr concentration {ital x}, when a field is applied. For small {ital x} the application of a field causes a significant broadening of the resistive transition---a behavior thought to be typical of high-{ital T}{sub {ital c}} cuprate superconductors---while for {ital x} exceeding 0.15, it simply causes a parallel shift of the curves to lower temperatures. From the analysis of the magnetoresistance above {ital T}{sub {ital c}} based on the theory of field-dependent fluctuation conductivity for layered materials, it is shown that the behavior of the field-induced resistive transition can be ascribed to the flux motion, especially when {bold H}{perpendicular}{bold c}. The analysis also shows that the out-of-plane Ginzburg-Landau coherence length {xi}{sub {ital c}}(0) increases systematically with {ital x} from 0.55 A at {ital x}=0.08 to 3 A at {ital x}=0.3, while the in-plane Ginsburg-Landau coherence length {xi}{sub {ital a}{ital b}}(0) is almost constant and {xi}{sub {ital a}{ital b}}(0)=31--33 A, irrespective of the value of {ital x} as long as {ital T}{sub {ital c}} remains high. The anisotropy {xi}{sub {ital a}{ital b}}(0)/{xi}{sub {ital c}}(0) estimated from these results exceeds 50 at low Sr concentrations and is still larger than 15 even for {ital x}{gt}0.1.

• OSTI ID: 5662980
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 44:1; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COPPER OXIDES
MAGNETORESISTANCE
HIGH-TC SUPERCONDUCTORS
LANTHANUM OXIDES
STRONTIUM OXIDES
COHERENCE LENGTH
CRITICAL FIELD
ELECTRIC CONDUCTIVITY
QUANTITY RATIO
QUATERNARY COMPOUNDS
SUPERCONDUCTING FILMS
TEMPERATURE DEPENDENCE
ALKALINE EARTH METAL COMPOUNDS
AMINES
AMMONIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
DIMENSIONS
ELECTRICAL PROPERTIES
FILMS
LANTHANUM COMPOUNDS
LENGTH
MAGNETIC FIELDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
STRONTIUM COMPOUNDS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties