Abstract
In this Letter, we calculate the electron-phonon coupling of the newly discovered superconductor using linear response. For pure LaFeAsO, the calculated electron-phonon coupling constant and logarithmic-averaged frequency give a maximum of 0.8 K, using the standard Migdal-Eliashberg theory. For the -doped compounds, we predict even smaller coupling constants. To reproduce the experimental , a 5–6 times larger coupling constant would be needed. Our results indicate that electron-phonon coupling is not sufficient to explain superconductivity in the whole family of Fe-As-based superconductors, probably due to the importance of strong-correlation effects.
- Received 18 March 2008
DOI:https://doi.org/10.1103/PhysRevLett.101.026403
©2008 American Physical Society