Density response of cuprates and renormalization of breathing phonons

P. Horsch; G. Khaliullin

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Density response of cuprates and renormalization of breathing phonons

P. Horsch·G. Khaliullin

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Abstract

We analyse the dynamical density fluctuation spectra for cuprates starting from the $t-J$ model in a slave-boson 1/N representation. The results obtained are consistent with diagonalization studies and show novel low-energy structure on the energy scale $J+δt$ due to the correlated motion of holes in a RVB spin liquid. The low-energy response implies an anomalous renormalization of several phonon modes. Here we discuss the renormalization of the highest breathing phonons in La$_{2-x}$Sr$_x$CuO$_4$.

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P. Horsch, G. Khaliullin. 2001-07-14. Density response of cuprates and renormalization of breathing phonons. https://arxiv.org/abs/cond-mat/0107323

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