title: Phonon lifetime investigation of anharmonicity and thermal conductivity of UO2 by neutron scattering and theory.
abstract: Inelastic neutron scattering measurements of individual phonon lifetimes and dispersion at 295 and 1200 K have been used to probe anharmonicity and thermal conductivity in UO2. They show that longitudinal optic phonon modes carry the largest amount of heat, in contrast to past simulations and that the total conductivity demonstrates a quantitative correspondence between microscopic and macroscopic phonon physics. We have further performed first-principles simulations for UO2 showing semiquantitative agreement with phonon lifetimes at 295 K, but larger anharmonicity than measured at 1200 K.
authors.affiliation: Oak Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge, Tennessee 37831, USA.
authors.forename: Judy W L
authors.initials: JW
authors.lastname: Pang
authors.affiliation: Chalk River Laboratories, National Research Council, Chalk River, Ontario, Canada K0J 1J0.
authors.forename: William J L
authors.initials: WJ
authors.lastname: Buyers
authors.affiliation: Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Aleksandr
authors.initials: A
authors.lastname: Chernatynskiy
authors.affiliation: Oak Ridge National Laboratory, Quantum Condensed Matter Division, Oak Ridge, Tennessee 37831, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Lumsden
authors.affiliation: Oak Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge, Tennessee 37831, USA.
authors.forename: Bennett C
authors.initials: BC
authors.lastname: Larson
authors.affiliation: Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Simon R
authors.initials: SR
authors.lastname: Phillpot