Pressure effects on the structural phase transitions and superconductivity of La[sub 2[minus][ital x]]Ba[sub [ital x]]CuO[sub 4] ([ital x]=0. 125)

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.6569· OSTI ID:6052112

Katano, S; Funahashi, S ^[1]; Mori, N; Ueda, Y ^[2]; Fernandez-Baca, J A ^[3]

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1. Department of Materials Science and Engineering, Japan Atomic Energy Research Institute, Tokai, Ibaraki 319-11 (Japan)
2. The Institute for Solid State Physics, The University of Tokyo, Roppongi, Minato-ku, Tokyo 106 (Japan)
3. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

Neutron-diffraction experiments have been performed to study the effects of hydrostatic pressure on the structural phase transitions of La[sub 2[minus][ital x]]Ba[sub [ital x]]CuO[sub 4] with [ital x]=0.125. The phase transition to the low-temperature tetragonal (LTT) structure is greatly suppressed by the application of pressure. The LTT transition temperature, observed at around 80 K at ambient pressure, decreases at the rate of about [minus]135 K/GPa, and this LTT phase disappears under a pressure of around 0.6 GPa. The superconducting properties of this compound under high pressure have also been investigated in detail by measurments of the ac magnetic susceptibility. The bulk superconducting transition temperature [ital T][sub [ital c]] remains constant at pressures of up to 0.5 GPa, and then increases with pressure at the rate of 10 K/GPa up to about 15 K at 1.5 GPa. From these results it is concluded that there is a clear correlation between the disappearance of the LTT phase and the enhancement of superconductivity. This conclusion supports earlier suggestions that there is a strong relationship between the crystal structure and superconductivity and that, in particular, the LTT phase is detrimental to the superconductivity in the La[sub 2[minus][ital x]]Ba[sub [ital x]]CuO[sub 4] system.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6052112
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:9; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360107 -- Metals & Alloys-- Superconducting Properties-- (1992-)
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL-PHASE TRANSFORMATIONS
DIFFRACTION
HIGH PRESSURE
HIGH-TC SUPERCONDUCTORS
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MEDIUM PRESSURE
NEUTRON DIFFRACTION
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PRESSURE DEPENDENCE
RARE EARTH COMPOUNDS
SCATTERING
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
VERY HIGH PRESSURE