Density Response of Cuprates and Renormalization of Breathing Phonons
نویسندگان
چکیده
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. 1
منابع مشابه
Density response of the t-J model and renormalization of breathing and half-breathing phonon modes: A slave-fermion calculation
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