Neutron-powder-diffraction study of nuclear and magnetic structure in YBa/sub 2/Cu/sub 3-//sub x/Co/sub x/O/sub 7+//sub y/ with x = 0. 84 and y = 0. 32
Neutron powder diffraction has been used to study the crystal structure and magnetic ordering of YBa/sub 2/Cu/sub 3-//sub x/Co/sub x/O/sub 7+//sub y/ with x = 0.84 and y = 0.32. Rietveld refinement of the crystal structure was carried out at 295 K (space group P4/mmm,a = 3.888 A,c = 11.636 A) and showed in particular that Co substitutes in the Cu(1) position of YBa/sub 2/Cu/sub 3/O/sub 7-//sub y/. Long-range, three-dimensional antiferromagnetism was observed up to a Neel temperature of about 405 K. All five detected magnetic peaks could be indexed on a wave vector ((1/2 1) / 2( 1/2) with h,k,l all odd, indicating a body-centered tetragonal magnetic unit cell with a/sub mag/ = a ..sqrt..2, c/sub mag/ = 2c. At 9 K the proposed magnetic structure has moments parallel to c antiferromagnetic ordering within both Cu and Co layers. Adjacent moments in neighboring Cu layers are antiparallel whereas the small moments found in the Co layers are parallel to their adjacent moments in the neighboring Cu layers. The ordered moment was 0.87..mu../sub B/ for the Cu layers and 0.16..mu../sub B/ in the Co layers, respectively. With increased temperature the ordered moments in the Co layers decrease faster than those in the Cu layer. At room temperature the ordered moment was (0.65(7))..mu../sub B/ for the Cu layers with no detectable ordered moment in the Co layers.
- Research Organization:
- Brookhaven National Laboratory, Upton, New York 11973-5000
- OSTI ID:
- 6934469
- Journal Information:
- Phys. Rev. B: Condens. Matter; (United States), Vol. 38:10
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM OXIDES
CRYSTAL STRUCTURE
MAGNETIC SUSCEPTIBILITY
NEUTRON DIFFRACTION
COBALT OXIDES
COPPER OXIDES
YTTRIUM OXIDES
ANTIFERROMAGNETISM
MAGNETIC PROPERTIES
SUPERLATTICES
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHALCOGENIDES
COBALT COMPOUNDS
COHERENT SCATTERING
COPPER COMPOUNDS
DIFFRACTION
MAGNETISM
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SCATTERING
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies
656100 - Condensed Matter Physics- Superconductivity