2009/10/31 by M. Raczkowski, Marcin Raczkowski, Peng Zhang +7
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Rare-earth and actinide compounds #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.81.054444
published as Phys. Rev. B 81, 054444 (2010) · 13 pages, 19 figures; added Ref.7 and comment on the scenario in which phonons couple to the f orbitals
openalex publication_date 2010/02/26 · arxiv created 2010/03/02 · arxiv updated 2010/03/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider models of heavy fermions in the strong coupling or local-moment limit and include phonon degrees of freedom on the conduction electrons. Due to the large mass or low coherence temperature of the heavy-fermion state, it is shown that such a regime is dominated by vertex corrections which leads to the complete failure of the Migdal theorem. Even at weak electron-phonon couplings, binding of the conduction electrons competes with the Kondo effect and substantially reduces the coherence temperature, ultimately leading to the Kondo breakdown. Those results are obtained using a combination of the slave-boson method and Migdal-Eliashberg approximation as well as the dynamical mean-field theory approximation.