Quasiparticles in high temperature superconductors: consistency of angle resolved photoemission and optical conductivity

Abstract

The consistency of angle-resolved photoemission and optical conductivity experiments on high temperature superconductors is examined. In the limit (apparently consistent with angle-resolved photoemission data) of an electron self energy with a weak momentum dependence and a strong frequency dependence formulae are derived which directly related quantities measured in the two experiments. Application of the formuale to optimally and overdoped $Bi_{2}Ca_{2}SrCu_{2}O_{8+\delta}$ shows that the total self energy inferred from photoemission measurements cannot be interpreted as a transport scattering rate (in agreement with work of Varma and Abrahams), but that the inelastic part may be so interpreted, if Landau parameter effects are non-negligible.