ISSN:
1089-7550
Quelle:
AIP Digital Archive
Thema:
Physik
Notizen:
Copper oxides have dominated superconductivity research since 1987. The interplay between superconductivity and magnetism lies at the center of the controversy concerning the appropriate microscopic model for their superconductivity. We have recently been exploring a broad new family of materials which represent the first true quaternary intermetallic superconductors. Although their superconducting Tc's are not competitive with the copper oxides, several of the members of the family have Tc's equivalent to the highest Tc's ever reported for intermetallic compounds. The materials are especially surprising in that they are not based on niobium alloys, but rather are based on the borides of nickel, palladium, and platinum. The presence of square planes of the normally magnetic transition metals nickel and palladium suggests that magnetism might play some role in the superconducting mechanism. There are experimental results on both sides of the magnetic/conventional mechanism question, and although at this time the community is leaning largely toward a conventional mechanism, this should still be considered an open question. The presence of superconductivity for some of the magnetic rare earth analogs results in interesting phenomena, especially in the case of HoNi2B2C where the magnetic transition on the Ho sublattice is very close to the superconducting Tc. This talk will serve as an introduction to the chemistry, structure, and basic physical properties of these new materials, and will draw on the results of other groups, as well to present a summary view of these materials. © 1996 American Institute of Physics.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1063/1.362149
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