The Heisenberg-Hubbard model is solved in the large-n limit to gain insight into its relevance to the coppper-oxide materials. A gapless disordered ground state is found for the Heisenberg model. Electronically induced orthorhombic-tetragonal symmetry breaking is observed as a function of doping, with the greatest tendency towards superconductivity occurring in the orthorhombic phase.
- Received 13 October 1987
- Published in the issue dated 1 March 1988
© 1988 The American Physical Society