Regensburg 2010 – wissenschaftliches Programm
TT 24.4: Vortrag
Mittwoch, 24. März 2010, 14:45–15:00, H19
High-Temperature optical behavior of Bi-based cuprates — •Georg Rohringer1, Alessandro Toschi1, Daniele Nicoletti2, Paolo Calvani2, Stefano Lupi2, Massimo Capone3, Giorgio Sangiovanni1, and Karsten Held1 — 1Institute of Solid State Physics, Vienna University of Technology — 2CNR-INFM Coeherentia and Department of Physics, University of Rome "La Sapienza" — 3CRS SMC, CNR-INFM and Department of Physics, University of Rome "La Sapienza"
The optical conductivity σ(ω) and the optical spectral weight W provide important information about the physical properties of strongly correlated systems[1,2]. This is the case for cuprates, where DMFT calculations have shown the important role of the quasiparticle renormalization factor Z, which manifests itself in a strong temperature (T) dependence of W at low T. We analyze here new experimental results for the normal phase of two Bi-based cuprates up to 500K. The comparison between our DMFT calculations and the experimental data for W allows for a full understanding of the observed deviation (∝ T4) from the low-temperature T2 behavior in the framework of a Sommerfeld expansion with strongly renormalized coefficients.
 L. Baldassarre et al., Phys.Rev. B 77, 113107 (2008)
 A. Toschi et al., Phys.Rev.Lett. 95, 097002 (2005)
 D. Nicoletti, O. Limaj, P. Calvani, G. Rohringer, et al. in preparation.