Conduction-electron spin density around Fe impurities in Cu above and below the Kondo temperature

Journal Article · Thu Jan 01 04:00:00 EST 1976 · Phys. Rev., B; (United States)

DOI:https://doi.org/10.1103/PhysRevB.13.379· OSTI ID:7365481

Boyce, J B; Slichter, C P

The nuclear resonances were observed for five shells of Cu atoms which are near neighbors to single Fe impurities in dilute alloys of CuFe. Each of the satellite shifts are linear in external magnetic field from 7 to 63 kG, and three have positive shifts while two have negative shifts. From line shape, intensity, and width, four of these satellites are identified as being due to the first, second, third, and fourth shells of neighbors. The satellite shifts, which are proportional to the conduction-electron spin density, are compared with the predictions of various theories in order to determine the values of the parameters involved in characterizing dilute magnetic alloys. It is found, using the theory of Jena and Geldart, that a good explanation of the spin density cannot be given unless the crystal-field splitting of the Fe d levels is taken into account. The energy-level parameters obtained are: the crystal-field splitting, 0.5 eV; virtual level width, 0.7 eV; Coulomb splitting, 5.6 eV. The magnetization distributed in the electron gas is shown to be aligned antiferromagnetically with the moment on the Fe atom and to be about nine times smaller than this moment. Four of these satellites were observed down to well below the 29/sup 0/K Kondo temperature, and, in each case, the shift scaled as 1/(T + 29). Thus, the spin density has the same temperature dependence as the bulk susceptibility, showing that contrary to some speculation there is no drastic change in the spatial polarization associated with the Kondo condensation.

• Research Organization: Univ. of Illinois, Urbana
• OSTI ID: 7365481
• Journal Information: Phys. Rev., B; (United States), Journal Name: Phys. Rev., B; (United States) Vol. 13:1; ISSN PLRBA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ALLOY SYSTEMS
ALLOYS
ANGULAR MOMENTUM
BINARY ALLOY SYSTEMS
COPPER ALLOYS
COPPER BASE ALLOYS
CRYSTAL FIELD
DILUTE ALLOYS
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
IMPURITIES
IRON ADDITIONS
IRON ALLOYS
KONDO EFFECT
LEPTONS
MAGNETIC FIELDS
MAGNETIC PROPERTIES
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
POLARIZATION
SPIN