Europhys. Lett.
Volume 75, Number 1, July 2006
Page(s) 146 - 152
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 09 June 2006
Europhys. Lett., 75 (1), pp. 146-152 (2006)
DOI: 10.1209/epl/i2006-10082-0

Renormalization group study of the electron-phonon interaction in high-Tc cuprates

H. C. Fu1, C. Honerkamp2, 3 and D.-H. Lee1, 4, 5

1  Department of Physics, University of California at Berkeley Berkeley, CA 94720, USA
2  Institute for Theoretical Physics, Universität Würzburg D-97074 Würzburg, Germany
3  Max-Planck-Institute for Solid State Research - D-70569 Stuttgart, Germany
4  Material Science Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA
5  Center for Advanced Study, Tsinghua University - Beijing 100084, PRC

received 20 March 2006; accepted in final form 17 May 2006
published online 9 June 2006

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-Tc 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 x2-y2 symmetry. All three sets of retarded interaction are driven to strong coupling by the magnetic fluctuations around $(\pi /a,\pi /a)$. 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.

74.20.Rp - Pairing symmetries (other than s-wave).
74.25.Kc - Phonons.
74.72.-h - Cuprate superconductors (high-Tc and insulating parent compounds).

© EDP Sciences 2006