Density response of cuprates and renormalization of breathing phonons

الأصل · EN

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 La₂₋ₓSrₓCuO₄.