Fermi surfaces

Abstract

This chapter, Fermi Surfaces, describes the development of both the theoretical and experimental techniques used to characterize the Fermi surfaces of all classes of layered superconductors. Depending upon the material, the date of its discovery, and the perfection of the samples, the experiments evolved from angle-resolved photoemission spectroscopy (ARPES) experiments on samples with easily cleaved surfaces to de Haas-van Alphen (dHvA) determinations of the Fermi surfaces. The theoretical characterizations varied from early density functional techniques to the present state of the art. Examples of the predicted and experimentally determined Fermi surfaces are presented for all classes of layered superconductors. Evidence for Fermi surface nesting and anisotropic charge-density wave gaps is presented. In many cases, only predictions are presently available, but in other cases, both ARPES and dHvA results are presented.