A square-lattice gauge-theory model for spin-charge-separated superconductivity is introduced. The phases of the spinon and holon order parameters couple gauge invariantly via a statistical gauge field, which arises from the implicit strong interaction physics. We find that physical electronic phase correlations show a superconductor–normal-metal phase transition of the Berezinskii-Kosterlitz-Thouless type, while statistical gauge-field excitations are strictly gapless. These results are discussed in the context of both the superconducting and the normal-state properties of the oxide superconductors.

• Received 14 July 1993

DOI:https://doi.org/10.1103/PhysRevB.49.3663