We consider a representation of the Hubbard model, in which the charge carriers are fermions and the spin carriers are bosons. We show that there exists a mean-field solution with a condensate of spin singlets and we characterize the low-temperature behavior of the quasiparticles. Finally, we calculate the tunneling spectrum for a normal-metal–resonating-valence-bond (RVB) state tunnel junction and suggest the tunneling experiment as a probe of the statistics of the RVB quasiparticles.

• Received 30 March 1989

DOI:https://doi.org/10.1103/PhysRevB.40.850