Boosting quantum Monte Carlo and alleviating sign problem by Gutzwiller projection

We present a scheme for projective quantum Monte Carlo (QMC) simulation that combines unbiased zero-temperature (projective) determinant QMC with variational Monte Carlo based on the Gutzwiller projected wave function. This approach is dubbed as Gutzwiller-projection QMC. Our numerical results demonstrate that the use of the Gutzwiller projected trial wave function significantly accelerates the convergence of computational results, thereby greatly reducing computational time in the simulation. Moreover, we provide an illustrative example showing that the sign problem is substantially mitigated in the Gutzwiller-projection QMC. We believe that the Gutzwiller-projection QMC opens up another pathway for enhancing efficiency and alleviating the sign problem in QMC simulations of interacting fermionic systems.