Magnetism and superconductivity of strongly correlated electrons on the triangular lattice

We investigate the phase diagram of the t−J model on a triangular lattice using a variational Monte Carlo approach. We use an extended set of Gutzwiller projected fermionic trial wave functions allowing for simultaneous magnetic and superconducting order parameters. We obtain energies at zero doping for the spin-1∕2 Heisenberg model in very good agreement with the best estimates. Upon electron doping (with a hopping integral t