Q-dependence of the spin fluctuations in the intermediate valence compound CePd3.
We report inelastic neutron scattering experiments on a single crystal of the intermediate valence compound CePd3. At 300 K the magnetic scattering is quasielastic, with half-width Γ = 23 meV, and is independent of momentum transfer Q. At low temperature, the Q-averaged magnetic spectrum is inelastic, exhibiting a broad peak centered near Emax = 55 meV. These results, together with the temperature dependence of the susceptibility, 4f occupation number, and specific heat, can be fit by the Kondo/Anderson impurity model. The low temperature scattering near Emax, however, shows significant variations with Q, reflecting the coherence of the 4f lattice. The intensity is maximal at (1/2, 1/2, 0), intermediate at (1/2, 0, 0) and (0, 0, 0), and weak at (1/2, 1/2, 1/2). We discuss this Q-dependence in terms of current ideas about coherence in heavy fermion systems.
Los Alamos National Laboratory, Los Alamos, NM 87545, USA. Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA.
V R
VR
Fanelli
J M
JM
Lawrence
E A
EA
Goremychkin
R
R
Osborn
E D
ED
Bauer
K J
KJ
McClellan
J D
JD
Thompson
C H
CH
Booth
A D
AD
Christianson
P S
PS
Riseborough
D002563:Cerium / Q000737:chemistry*; D003198:Computer Simulation; D060526:Magnetic Fields; D008956:Models, Chemical; D010165:Palladium / Q000737:chemistry*; D013113:Spin Labels; D013696:Temperature
D013113:Spin Labels; D002563:Cerium; D010165:Palladium