Temperature and doping dependence of the high-energy kink in cuprates

Phys Rev Lett. 2008 Jan 25;100(3):036402. doi: 10.1103/PhysRevLett.100.036402. Epub 2008 Jan 24.


It is shown that spectral functions within the extended t-J model, evaluated using the finite-temperature diagonalization of small clusters, exhibit the high-energy kink in single-particle dispersion consistent with recent angle-resolved photoemission results on hole-doped cuprates. The kink and waterfall-like features persist up to large doping and to temperatures beyond J; hence, the origin can be generally attributed to strong correlations and incoherent hole propagation at large binding energies. In contrast, our analysis predicts that electron-doped cuprates do not exhibit these phenomena in photoemission.