NIST Technicalendar Single Item Display: Meeting at NIST Item ID: 011041Dan0.70064538

1/14/03 10:45 AM - NIST SEMINAR: Oxygen Phonon Anomalies in Strongly Correlated Perovskite Oxides

Remarkable electronic properties of many perovskite oxides such as high temperature superconductivity and colossal magnetoresistance (CMR) are of both practical and fundamental interest. Oxygen vibrations in these materials are strongly coupled to electronic degrees of freedom as evidenced by a number of experimental and theoretical results. Thus detailed measurements of phonons with oxygen character can be used as a sensitive probe of electronic states. Results of several neutron scattering studies of phonon dispersions at different temperatures in YBa2Cu3O7, Ba0.6K0.4BiO3, La1.69Sr0.31NiO4, and La0.7Sr0.3MnO3 will be presented. Effects of superconductivity, charge inhomogeneities including stripes, and the CMR transition on the oxygen vibrations will be discussed.

Dmitry Reznik , Laboratoire Leon Brillouin.

235 Building, Room E100. (NIST Contact: Dan Neumann, 301-975-5252, dan@nist.gov)