Estimation of matrix-element effects and determination of the Fermi surface in Bi2Sr2CaCu2O8+δ systems using angle-scanned photoemission spectroscopy

Abstract
The strong dependence of the momentum distribution of the photoelectrons on experimental conditions raises the question as to whether angle-resolved photoemission spectroscopy is able to provide an accurate reflection of the Fermi surface in Bi-based cuprate superconductors. In this paper we experimentally prove that the main contribution to the intensity variation comes from matrix-element effects and develop an approach to overcome this problem. We introduce a concept of “self-normalization” that makes the spectra essentially independent of both the matrix elements and particular experimental parameters. On the basis of this concept we suggest a simple and precise method of Fermi-surface determination in quasi-two-dimensional systems.