Features in Quasi—particle Excitations and Tunnelling Spectra due to Coupling to Spin Fluctuations in High—Tc Cuprates

In a self-consistent mean-field treatment of the two-dimensional t-t‘-J model,we theoretically examine the coupling of in-plane quasi-particles to the antiferromagnetic spin fluctuations in high-Tc superconductors,which renormalizes the fermionic self-energy.We reproduce the characteristic peak-dip-hump structure observed not only in angly-resolved photoemission spectroscopy,but also in superconductor-insulator-normal metal unctions and scanning tunnelling microscopy experiments.We consider the evolution of this structure with doping.It is shown that this kind of coupling can account for many anomalous properties of high-Tc superconductors in superconducting states.