Absorption at radio frequencies in superconducting Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub /ital y//

Journal Article · Tue Aug 01 00:00:00 EDT 1989 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.344450· OSTI ID:6052111

Ducharme, S; Durny, R; Hautala, J; Zheng, D J; Taylor, P C; Symko, O G; Kulkarni, S

The large magnetic-field-dependent ac absorption in superconducting Y/sub 1/ Ba/sub 2/ Cu/sub 3/ O/sub /ital y// ceramics and powders decreases slowly with increasing frequency in the range 2--16 MHz. The magnetic-field-dependent ac absorption is observed below /ital T//sub /ital c// in superconducting Y/sub 1/ Ba/sub 2/ Cu/sub 3/ O/sub /ital y// ceramics, powders and twinned crystals and in (La,Sr)/sub 2/ CuO/sub 4/ and BaPb/sub 0.75/ Bi /sub 0.25/ CuO/sub 3/ powders and appears to contain distinct contributions from trapped flux and/or intragrain tunnel junctions and from ordinary superconductor surface impedance. The contribution from trapped flux and/or intragrain tunnel junctions is important in dc magnetic fields of up to approximately 20 G at all temperatures below /ital T//sub /ital c//. There is an identifiable modulated ac absorption which changes slowly over more than 12 kG at low temperatures and which we propose is primarily caused by the ac surface impedance with possible contributions from the critical state. A twinned crystal of Y/sub 1/ Ba/sub 2/ Cu/sub 3/ O/sub /ital y// exhibits the same ac absorption except that it has an anisotropic dependence on the applied dc magnetic field.

• Research Organization: Department of Physics, University of Utah, Salt Lake City, Utah 84112(US); Ceramatec, Inc., Salt Lake City, Utah 84115
• OSTI ID: 6052111
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 66:3; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTRA
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CERAMICS
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRYSTALS
ELECTRIC IMPEDANCE
ELECTROMAGNETIC RADIATION
FREQUENCY RANGE
IMPEDANCE
MAGNETIC FIELDS
MHZ RANGE
MHZ RANGE 01-100
OXIDES
OXYGEN COMPOUNDS
POWDERS
RADIATIONS
RADIOWAVE RADIATION
SPECTRA
SUPERCONDUCTORS
SURFACES
TRANSITION ELEMENT COMPOUNDS
TWINNING
YTTRIUM COMPOUNDS
YTTRIUM OXIDES