Lanczos steps to improve variational wave functions

@article{Becca2014LanczosST,
  title={Lanczos steps to improve variational wave functions},
  author={Federico Becca and Wenjun Hu and Yasir Iqbal and Alberto Parola and Didier Poilblanc and Sandro Sorella},
  journal={arXiv: Strongly Correlated Electrons},
  year={2014}
}
Gutzwiller-projected fermionic states can be efficiently implemented within quantum Monte Carlo calculations to define extremely accurate variational wave functions for Heisenberg models on frustrated two-dimensional lattices, not only for the ground state but also for low-energy excitations. The application of few Lanczos steps on top of these states further improves their accuracy, allowing calculations on large clusters. In addition, by computing both the energy and its variance, it is… 

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