Evidence for two pairing energies from nuclear spin-lattice relaxation in superconducting Ba/sub 2/YCu/sub 3/O/sub 7-//sub delta/

Journal Article · Mon Oct 19 00:00:00 EDT 1987 · Phys. Rev. Lett.; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.59.1860· OSTI ID:5923400

Warren, Jr, W W; Walstedt, R E; Brennert, G F; Espinosa, G P; Remeika, J P

We report /sup 63/Cu nuclear spin-lattice relaxation data for Ba/sub 2/YC/sub 3/O/sub 7-//sub delta/ in the superconducting state obtained by nuclear quadrupole resonance in zero applied magnetic field. The temperature dependences of the relaxation rates reveal striking differences in the excitation spectra for quasiparticles on the chain-forming Cu1 and planar Cu2 lattice sites, corresponding to substantially different pairing energies for electrons on the planes and chains. Values of the gap ratio 2..delta../kT/sub c/ 8.3 and 2.4 are obtained for the Cu1 and Cu2 sites, respectively.

• Research Organization: AT and T Bell Laboratories, Murray Hill, New Jersey 07974
• OSTI ID: 5923400
• Journal Information: Phys. Rev. Lett.; (United States), Journal Name: Phys. Rev. Lett.; (United States) Vol. 59:16; ISSN PRLTA
• 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
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER 63
COPPER COMPOUNDS
COPPER ISOTOPES
COPPER OXIDES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON PAIRS
INTERMEDIATE MASS NUCLEI
ISOTOPES
LOW TEMPERATURE
NUCLEI
ODD-EVEN NUCLEI
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RELAXATION
SPIN-LATTICE RELAXATION
STABLE ISOTOPES
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
YTTRIUM COMPOUNDS
YTTRIUM OXIDES