Superconducting materials with electron pairs localized on lattice ions
We propose the following classification scheme for superconductors, depending on the probable type of electron--electron interaction: A) Semiconductors containing impurities with negative Hubbard energy in which pairs exist in r-space when T>T/sub c/: Pb/sub 1-x/Tl/sub x/Te, Ba(Pb/sub 1-x/Bi/sub x/)O/sub 3/xxx. In this case the superconducting phase transition must compete with the ordering of ions having different charges: Pb/sub 1-x/In/sub x/Te. B) Metals near the metal--insulator transition with virtual two-electron levels near the Fermi level: Na/sub x/WO/sub 3/. C) Metals containing ''active'' atoms (ions) with an odd number of electrons and a small Hubbard energy. We suggest that the contribution of diamagnetic polar configurations to the total energy of the metal can increase when coherent states are formed: Nb, La/sub 3/S/sub 4/, Nb/sub 1-x/Ti/sub x/xxx.
- Research Organization:
- All-Union Scientific-Research, Design-Planning, and Technological Institute of Current Sources, Leningrad
- OSTI ID:
- 5497819
- Journal Information:
- Sov. Phys. - Solid State (Engl. Transl.); (United States), Vol. 25:7
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
SUPERCONDUCTIVITY AND SUPERFLUIDITY
SUPERCONDUCTORS
CLASSIFICATION
ELECTRON-ELECTRON INTERACTIONS
ELECTRON PAIRS
FERMI LEVEL
IMPURITIES
METALS
ELEMENTS
ENERGY LEVELS
INTERACTIONS
LEPTON-LEPTON INTERACTIONS
PARTICLE INTERACTIONS
656101* - Solid State Physics- Superconductivity- General Theory- (-1987)