Disorder tuning of non-Fermi-liquid behaviour inP. Giudicelli1, 2, U. Killer3, J. W. Taylor4, S. J. Levett4, A. Otop5, E.-W. Scheidt3, A. Stunault2 and N. Bernhoeft1
1 DRFMC, CEA-Grenoble - F-38054 Grenoble, France
2 Institut Laue Langevin - F-38042 Grenoble, France
3 Institut für Physik, Universität Augsburg - D-86159 Augsburg, Germany
4 ISIS Facility, RAL - Didcot, Oxfordshire, UK
5 Institut für Physik, TU Braunschweig - D-38106 Braunschweig, Germany
received 22 September 2004; accepted in final form 7 December 2004
published online 26 January 2005
Neutron inelastic scattering has been used to examine the space-time magnetic correlation function in the non-Fermi-liquid compound . In contrast with the results obtained previously on as-cast samples, the response of carefully annealed material shows a simple exponential time dependence. These microscopic measurements confirm an earlier conjecture based on annealing experiments that, whilst atomic disorder is not the origin of non-Fermi-liquid behaviour in , the order-disorder equilibrium may, however, in a similar manner to the use of applied magnetic field, pressure and composition, be used as a tuning parameter to achieve non-Fermi-liquid response.
71.10.Hf - Non-Fermi-liquid ground states, electron phase diagrams and phase transitions in model systems.
71.27.+a - Strongly correlated electron systems; heavy fermions.
75.20.Hr - Local moment in compounds and alloys; Kondo effect, valence fluctuations, heavy fermions.
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