Preparation and superconducting properties of La/sub 1.8/Sr/sub 0.2/CuO/sub 4/ and YBa/sub 2/Cu/sub 3/O/sub 6.5/
Creators
- 1. Kernforschungszentrum Karlsruhe, Karlsruhe
Description
For La/sub 1.8/Sr/sub 0.2/CuO/sub 4/ onsets up to 55 K and midpoints of 42 K are observed. Single phase YBa/sub 2/Cu/sub 3/O/sub 6.5/ samples show onsets near 125 K with midpoints between 102 and 112 K. On non-equilibrium multi-phase samples of Y/sub 1.2/Ba/sub 0.8/CuO/sub 4/ a decrease of the resistance starting near 240 K is observed. A positive initial pressure coefficient is found for La/sub 1.8/Sr/sub 0.2/CuO/sub 4/ and YBa/sub 2/Cu/sub 3/O/sub 6.5./T/sub c/ onsets up to 120 K (zero resistance :100K) are observed by substituting F for O in YBa/sub 2/Cu/sub 3/O/sub 6/F/sub 1/. Freshly annealed samples of YBa/sub 2/Cu/sub 3/O/sub 6.5/ are extremely metastable, the T/sub c/ midpoints initially at 112 K moving to 105 K after 12h in air. XPS and UPS photoemission experiments show only a Cu/sup 2+/ state. La/sub 1.8/Sr/sub 0.2/CuO/sub 4/ is the most irradiation sensitive superconductor known so far
Additional details
Publishing Information
- Publisher
- Materials Research Society.
- Imprint Place
- Pittsburgh, PA (USA)
- Imprint Title
- Proceedings of symposium S at the 1987 Spring meeting of the MRS on high temperature superconductors (Extended Abstracts)
- Journal Page Range
- p. 141-144.
Conference
- Title
- Spring meeting of the Materials Research Society.
- Dates
- 21-25 Apr 1987.
- Place
- Anaheim, CA (USA).
INIS
- Country of Publication
- United States
- Country of Input or Organization
- United States
- INIS RN
- 18094172
- Subject category
- S36: MATERIALS SCIENCE; S37: INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY;
- Resource subtype / Literary indicator
- Conference
- Descriptors DEI
- AIR; CHEMICAL PREPARATION; COPPER OXIDES; LANTHANUM OXIDES; LOW TEMPERATURE; PHOTOELECTRON SPECTROSCOPY; PHOTOEMISSION; SENSITIVITY; STRONTIUM OXIDES; SUPERCONDUCTIVITY; SUPERCONDUCTORS; TEMPERATURE DEPENDENCE; TRANSITION TEMPERATURE; VERY LOW TEMPERATURE; X-RAY SPECTROSCOPY; YTTRIUM OXIDES
- Descriptors DEC
- ALKALINE EARTH METAL COMPOUNDS; CHALCOGENIDES; COPPER COMPOUNDS; ELECTRIC CONDUCTIVITY; ELECTRICAL PROPERTIES; ELECTRON SPECTROSCOPY; EMISSION; FLUIDS; GASES; LANTHANUM COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; RARE EARTH COMPOUNDS; SECONDARY EMISSION; SPECTROSCOPY; STRONTIUM COMPOUNDS; SYNTHESIS; THERMODYNAMIC PROPERTIES; TRANSITION ELEMENT COMPOUNDS; YTTRIUM COMPOUNDS