Kordyuk A A, Borisenko S V, Zabolotnyy V B, Geck J, Knupfer M, Fink J, Büchner B, Lin C T, Keimer B, Berger H, Pan A V, Komiya Seiki, Ando Yoichi
Institut für Festkoerper und Werkstofforschung Dresden, Post Office Box 270116, D-01171 Dresden, Germany.
Phys Rev Lett. 2006 Jul 7;97(1):017002. doi: 10.1103/PhysRevLett.97.017002. Epub 2006 Jul 6.
Applying the Kramers-Kronig consistent procedure, developed earlier, we investigate in detail the formation of the quasiparticle spectrum along the nodal direction of high-Tc cuprates. The heavily discussed "70 meV kink" on the renormalized dispersion exhibits a strong temperature and doping dependence when purified from structural effects such as bilayer splitting, diffraction replicas, etc. This dependence is well understood in terms of fermionic and bosonic constituents of the self-energy. The latter follows the evolution of the spin-fluctuation spectrum, emerging below some doping dependent temperature and sharpening below Tc, and is mainly responsible for the formation of the kink in question.
