Gauge theory of high-temperature superconductors and strongly correlated Fermi systems

Abstract
In this paper we show that the development of resonating-valence-bond correlations and the subsequent superconducting order in the high-Tc oxide superconductors are described by an U(1) lattice-gauge theory. The insulating state has an almost-local gauge symmetry and doping changes this to a global symmetry, which is spontaneously broken at low temperatures, resulting in superconductivity. New topological excitations associated with the singlet field are found.