arXiv:cond-mat/0509072 · Europhysics Letters (EPL)
Renormalization group study of the electron-phonon interaction in high- T c cuprates
Henry Fu, Carsten Honerkamp A, D. H. Lee
Abstract
We generalize the numerical renormalization group (RG) scheme of Honerkamp et al. ( Phys. Rev. B , 63 (2001) 035109), Zanchi et al. ( Europhys. Lett. , 44 (1997) 235; Phys. Rev. B , 61 (2000) 13609) and Halboth et al. ( Phys. Rev. Lett. , 85 (2000) 5162) to study the phonon-mediated retarded interactions in the high- T c cuprates. We find that three sets of phonon-mediated retarded quasiparticle scatterings grow under RG flow. These scatterings share the following common features: 1) the initial and final quasiparticle momenta are in the antinodal regions, and 2) the scattering amplitudes have a x 2 - y 2 symmetry. All three sets of retarded interaction are driven to strong coupling by the magnetic fluctuations around (π/ a ,π/ a ). After growing strong, these retarded interaction will trigger density wave orders with d -wave symmetry. However, due to the d -wave form factor they will leave the nodal quasiparticle unaffected. We conclude that the main effect of electron-phonon coupling in the cuprates is to promote these density wave orders.