Doping dependence of density response and bond-stretching phonons in cuprates

Physica B Condensed Matter (Impact Factor: 1.28). 01/2005; 359-361:620-622. DOI: 10.1016/j.physb.2005.01.170
Source: arXiv

ABSTRACT We explain the anomalous doping dependence of zone boundary $(\pi,0)$ and $(\pi,\pi)$ bond-stretching phonons in the high-temperature superconductor La$_{2-\delta}$Sr$_{\delta}$CuO$_4$ in the doping range $0<\delta<0.35$. Our calculations are based on a theory for the density response of doped Mott-Hubbard insulators. Comment: 2 pages, 3 figures, SCES conference, Karlsruhe 2004

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