Antiferromagnetism in the high-T/sub c/ related compounds (invited)

Journal Article · Fri Apr 15 04:00:00 EDT 1988 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.340555· OSTI ID:5327594

Sinha, S K; Moncton, D E; Johnston, D C; Vaknin, D; Shirane, G; Stassis, C

Magnetic susceptibility measurements on La/sub 2/CuO/sub 4-//sub y/ have revealed maxima in temperature indicative of antiferromagnetic ordering. Powder diffraction measurements have demonstrated the existence of superlattice peaks at temperatures below those corresponding to the susceptibility maxima, and polarized neutron measurements have confirmed that the peaks are indeed of magnetic origin. The deduced antiferromagnetic structure in the orthorhombic (Cmca) phase of La/sub 2/CuO/sub 4-//sub y/ consists of ferromagnetic sheets of Cu atoms in the b-c plane which are alternating in sign along the a axis (100). The moment is parallel to the c axis. The Neel temperature is extremely sensitive to the oxygen deficiency y and decreases rapidly to zero as y goes from 0.03 to 0. The saturated moment is approx. =0.4 ..mu../sub B//Cu atom for samples with the highest T/sub N/ (290 K). Antiferromagnetic spin fluctuations have also been observed by polarized neutron scattering in the paramagnetic phase above T/sub N/. Recent results obtained on magnetic ordering in the YBa/sub 2/Cu/sub 3/O/sub 6-//sub y/ family of compounds are also discussed, together with the possible implications for novel superconductivity mechanisms.

• Research Organization: Exxon Research and Engineering Company, Annandale, New Jersey 08801
• OSTI ID: 5327594
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 63:8; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
ANTIFERROMAGNETISM
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
DATA
EXPERIMENTAL DATA
FERROMAGNETISM
HIGH TEMPERATURE
INFORMATION
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MAGNETISM
MEDIUM TEMPERATURE
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTH COMPOUNDS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS