Superexchange mechanism and dwave superconductivity
Abstract
We have formulated an auxiliaryboson meanfield theory consistent with the SU(2) symmetry of the Heisenberg model. At half filling, we find an infinite number of solutions related by the symmetry. Away from half filling the kinetic energy, acting as a symmetrybreaking field, selects a superconducting state of dwave symmetry. The meanfield theory describes bosons and fermions with finite kinetic energy close to half filling. We derive selfconsistent equations for the superconducting transition temperature T_{c}. We find that T_{c} vanishes at large and small filling factors.
 Publication:

Physical Review B
 Pub Date:
 September 1988
 DOI:
 10.1103/PhysRevB.38.5142
 Bibcode:
 1988PhRvB..38.5142K
 Keywords:

 74.20.z;
 71.28.+d;
 74.90.+n;
 74.70.Vy;
 Theories and models of superconducting state;
 Narrowband systems;
 intermediatevalence solids;
 Other topics in superconductivity