Regensburg 2010 – wissenschaftliches Programm
TT 24.11: Vortrag
Mittwoch, 24. März 2010, 17:15–17:30, H19
Plasmons and interband transitions of Sr14−xCaxCu24O41 investigated by electron energy-loss spectroscopy — •Friedrich Roth, Martin Knupfer, Christian Hess, and Bernd Büchner — IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany
Electron energy-loss spectroscopy has been used to investigate the loss-function between 0 and 70 eV of singel-crystalline Sr14−xCaxCu24O41, composed of two-leg Cu2O3 ladders and edge-sharing CuO2 chains, with various compositions. We found significant exitations in the low-energy range which are different for momentum transfer q parallel to the a- and c-axes. Comparison with reflectivity data from literature  shows a good agreement with our data. Also the disperions of a charge-carrier plasmon like in Bi2Sr2CaCu2O8  was obeserved for Sr3Ca11Cu24O41.
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