Bosonic Spectral Function and the Electron-Phonon Interaction in HTSC Cuprates

Figure 14

(top) Quasiparticle dispersion of Bi2212, Bi2201, and LSCO along the nodal direction, plotted versus the momentum 𝑘 for (a)–(c) different doping, and (d)-(e) different 𝑇; black arrows indicate the kink energy; the red arrow indicates the energy of the 𝑞=(𝜋,0) oxygen stretching phonon mode; inset of (e) shows 𝑇-dependent Σ^ for optimally doped Bi2212; (f) shows doping dependence of the effective coupling constant 𝜆^ along (0,0)−(𝜋,𝜋) for the different HTSC oxides. From [91]. (bottom) Quasiparticle dispersion 𝐸(𝑘) in the normal state (a1, b1, c), at 107 K and 115 K, along various directions 𝜙 around the antinodal point. The kink at 𝐸=40meV is shown by the horizontal arrow. (a2 and b2) are 𝐸(𝑘) in the superconducting state at 10 K with the shifted kink to 70meV. (d) kink positions as a function of 𝜙 in the antinodal region. From [134].