Magnetism in the heavy-electron superconductors UPt/sub 3/ and URu/sub 2/Si/sub 2/

Journal Article · Thu Dec 01 04:00:00 EST 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.38.11193· OSTI ID:6605231

Norman, M R; Oguchi, T; Freeman, A J

The nature of magnetism in the heavy-electron superconductors UPt/sub 3/ and URu/sub 2/Si/sub 2/ is investigated by using a spin-orbit generalized variant of local-spin-density (LSD) theory to calculate the self-consistent moment-polarized electronic structure and the dynamic (bare-band) susceptibility. It is shown that the direction of the magnetic moment is predicted correctly. The size of the moment, however, is 0.8..mu../sub B/ in UPt/sub 3/ and 1.2..mu../sub B/ in URu/sub 2/Si/sub 2/, i.e., a factor of 40 larger than experiment. It is noted, however, that the experimental moment of (0.65 +- 0.1)..mu../sub B/ for Th- or Pd-doped UPt/sub 3/ is close to the theoretical value. The static susceptibility, chi(q), is predicted to be weakly dependent on q except for UPt/sub 3/, where a peak is found at q = (..pi../c)(0,0,2): in general agreement with neutron-scattering data at high frequencies. The low-frequency anomalies in the neutron data which lead to magnetic ordering are not seen in the calculated dynamic susceptibility, but can be understood in terms of a moment-moment interaction. An explanation for these conflicting data is offered based on the interaction of itinerant quasiparticle and local-moment degrees of freedom at low temperatures, which leads to a renormalization of the LSD spin-spin response function.

• Research Organization: Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439
• OSTI ID: 6605231
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 38:16; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ACTINIDE ALLOYS
ALLOYS
BAND THEORY
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRONIC STRUCTURE
ENERGY LEVELS
FERMI LEVEL
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
PHYSICAL PROPERTIES
PLATINUM ALLOYS
PLATINUM METAL ALLOYS
RUTHENIUM ALLOYS
SILICON ALLOYS
SUPERCONDUCTIVITY
SUPERCONDUCTORS
URANIUM ALLOYS
URANIUM BASE ALLOYS