A model with electron–phonon interaction for high-Tc d-wave cuprates

Abstract Within the BCS framework a model with d-wave symmetry is introduced to describe high- T c superconductor cuprates. The electron–phonon interaction is considered as the dominant cause of superconductivity. In order to increase the electronic density of states at the Fermi level, an anomalous occupation, has been proposed. The phonon available energy is introduced by the half-breathing phonons. Numerical results for the coupling parameter λ , the energy gap Δ 0 , and parameters of the model, as a function of doping, in the (0.105,  0.22) range, are obtained for the cuprate La 2−x Sr x CuO 4 . The λ values obtained are in the intermediate and the weak coupling region and the experimental results for the gap Δ 0 are reproduced with our model.