Within the intermediate-coupling theory, the quasiparticle weight Z of one hole injected into the undoped antiferromagnetic ground state is studied. We find that, for the hole located at the quasiparticle band minimum with momentum k0=(±π/2, ±π/2), Z is finite. By comparing the results obtained by the self-consistent Born approximation, we show that the intermediate-coupling theory for Z is appropriate only when J/t?1.6. Finally, the reason why this approach fails in the small-J case will also be clarified.
Relation:
Physical Review B - Condensed Matter and Materials Physics Volume 55, Issue 1, 1 January 1997, Pages 56-58
