Phenomenology of the low-energy spectral function in high-Tc superconductors

Abstract

We introduce a simple phenomenological form for the self-energy which allows us to extract important information from angle-resolved photoemission data on the high-Tc superconductor Bi2Sr2CaCu2O8 for binding energies of order the spectral gap. First, we find a rapid suppression of the single particle scattering rate below Tc for all doping levels. Second, we find that in the overdoped materials the gap Δ at all k points on the Fermi surface has significant temperature dependence and vanishes near Tc. In contrast, in the underdoped samples such behavior is found only at k points close to the diagonal. Near (π,0), Δ is essentially T independent in the underdoped samples. The filling-in of the pseudogap with increasing T is described by a broadening proportional to T−Tc, which is naturally explained by pairing correlations above Tc.

Source-reported materials — not catalogue approval

Similar papers