  Based on the SU(2) slave-boson approach to the t-J Hamiltonian, we examine
the cause of the sharp peaks('quasiparticle' peaks) in the observed spectral
functions in high $T_c$ cuprates. The computed results reveal that the spectral
weight of the sharp peaks increases with hole doping rate in agreement with
observation. It is shown that the observed sharp peaks are attributed to the
enhancement of spinon pairing(spin singlet pair formation) by the presence of
holon pair bosons in the superconducting state.
