Resonating-valence-bond wave function for the two-dimensional Heisenberg model on a triangular lattice

A resonating-valence-bond (RVB) wave function for the triangular lattice is constructed by following the renormalized Hamiltonian approach (or Gutzwiller approximation) successfully developed for the square lattice. This wave function is then used to calculate the ground-state energy by using the variational Monte Carlo method. Comparison with results of other trial wave functions is discussed. Energy of this paramagnetic RVB state is not as low as other antiferromagnetically ordered wave functions. A flux-phase state similar to the RVB state is also presented. This state with one-quarter flux quantum per plaquette breaks time-reversal symmetry.