title: Direct observation of paramagnons in palladium.
abstract: We report an inelastic neutron scattering study of the spin fluctuations in the nearly ferromagnetic element palladium. Dispersive over-damped collective magnetic excitations or "paramagnons" are observed up to 128 meV. We analyze our results in terms of a Moriya-Lonzarich-type spin-fluctuation model and estimate the contribution of the spin fluctuations to the low-temperature heat capacity. In spite of the paramagnon excitations being relatively strong, their relaxation rates are large. This leads to a small contribution to the low-temperature electronic specific heat.
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom.
authors.forename: R
authors.initials: R
authors.lastname: Doubble
authors.forename: S M
authors.initials: SM
authors.lastname: Hayden
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Dai
authors.forename: H A
authors.initials: HA
authors.lastname: Mook
authors.forename: J R
authors.initials: JR
authors.lastname: Thompson
authors.forename: C D
authors.initials: CD
authors.lastname: Frost