Horsch, P. & Khaliullin, G. Doping dependence of density response and bond-stretching phonons in cuprates. Physica B 359-361, 620-622

Physica B Condensed Matter (Impact Factor: 1.32). 01/2005; 359-361:620-622. DOI: 10.1016/j.physb.2005.01.170
Source: arXiv


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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Available from: Peter Horsch, Nov 21, 2012
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    • "In one of the first theoretical papers considering lattice vibrations in cuprates the phonon softening was found by exact diagonalization technique in the model where effective Hamiltonian was obtained from the three-band model [162]. Softening of the breathing q = (π, π) and halfbreathing q = (π, 0) phonons was calculated in [83] [84] [87] [92]. The calculation predicted dependence of the softening on the doping concentration which was later confirmed experimentally [95]. "
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