title: Magnetic fluctuations at a field-induced quantum phase transition.
abstract: We report an inelastic neutron-scattering study at the field-induced magnetic quantum phase transition of CeCu5.8Au0.2. The data can be described better by the spin-density-wave scenario than by a local quantum critical point, while the latter scenario was shown to be applicable to the zero-field concentration-tuned quantum phase transition in CeCu6-xAux for x=0.1. This constitutes direct microscopic evidence for a difference in the quantum fluctuation spectra at a magnetic quantum critical point driven by different tuning parameters.
authors.affiliation: Max-Planck-Institut für Chemische Physik fester Stoffe, D-01187 Dresden, Germany.
authors.forename: O
authors.initials: O
authors.lastname: Stockert
authors.forename: M
authors.initials: M
authors.lastname: Enderle
authors.forename: H V
authors.initials: HV
authors.lastname: Löhneysen