Study of hole pair condensation based on the SU(2) slave-boson approach tothe t-J Hamiltonian

We present a phase diagram of high T-c cuprates involving the holon pair co ndensation based on the SU(2) slave-boson approach to the t-J Hamiltonian. Owing to the proper account of low-energy phase fluctuations by the SU(2) t heory, we find that the predicted holon pairing temperature (the supercondu cting transition temperature) is in better agreement with experiments, comp ared to the U(1) mean field theory. (C) 2000 Elsevier Science B.V. All righ ts reserved.