Oxygen isotope effect on Neel temperature in various antiferromagnetic cuprates
- Morris Research Inc., 1918 University Avenue, Berkeley, California 94704 (United States)
Oxygen isotope effect on Neel temperature ([ital T][sub [ital N]]) has been studied in the antiferromagnetic cuprates La[sub 2]CuO[sub 4], Gd[sub 2]CuO[sub 4], Gd[sub 1.9]Ce[sub 0.1]CuO[sub 4], and CuO. For stoichiometric La[sub 2]CuO[sub 4] with [ital T][sub [ital N]][similar to]310 K, the Neel temperature of the [sup 18]O samples is [similar to]1.8 K lower than the [sup 16]O samples. For oxygen-annealed La[sub 2]CuO[sub 4] samples (in 0.10 and 0.15 bar oxygen partial pressures), the Neel temperatures of the [sup 18]O samples are [similar to]3.3--4.7 K lower than the [sup 16]O samples. For La[sub 2]CuO[sub 4] annealed in 0.6 bar oxygen, the Neel temperatures of the [sup 16]O and [sup 18]O samples are nearly equal due to segregation into oxygen-rich and oxygen-poor phases. For the other antiferromagnetic cuprates (which lack apical oxygen), we find a negligible oxygen isotope effect on [ital T][sub [ital N]]. We suggest that the observed oxygen isotope effect on [ital T][sub [ital N]] of La[sub 2]CuO[sub 4] originates from the oxygen-mass dependences of [ital J] (in-plane antiferromagnetic exchange energy) due to the nonadiabatic motion of apical oxygen.
- OSTI ID:
- 6716224
- Journal Information:
- Physical Review, B: Condensed Matter; (United States), Vol. 50:6; ISSN 0163-1829
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CUPRATES
ANTIFERROMAGNETISM
ISOTOPE EFFECTS
GADOLINIUM OXIDES
HIGH-TC SUPERCONDUCTORS
LANTHANUM OXIDES
CERIUM ADDITIONS
NEEL TEMPERATURE
OXYGEN 16
OXYGEN 18
TRANSITION TEMPERATURE
ALLOYS
CERIUM ALLOYS
CHALCOGENIDES
COPPER COMPOUNDS
EVEN-EVEN NUCLEI
GADOLINIUM COMPOUNDS
ISOTOPES
LANTHANUM COMPOUNDS
LIGHT NUCLEI
MAGNETISM
NUCLEI
OXIDES
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PHYSICAL PROPERTIES
RARE EARTH ADDITIONS
RARE EARTH ALLOYS
RARE EARTH COMPOUNDS
STABLE ISOTOPES
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
360207* - Ceramics
Cermets
& Refractories- Superconducting Properties- (1992-)