title: Reptation quantum Monte Carlo algorithm for lattice Hamiltonians with a directed-update scheme.
abstract: We provide an extension to lattice systems of the reptation quantum Monte Carlo algorithm, originally devised for continuous Hamiltonians. For systems affected by the sign problem, a method to systematically improve upon the so-called fixed-node approximation is also proposed. The generality of the method, which also takes advantage of a canonical worm algorithm scheme to measure off-diagonal observables, makes it applicable to a vast variety of quantum systems and eases the study of their ground-state and excited-state properties. As a case study, we investigate the quantum dynamics of the one-dimensional Heisenberg model and we provide accurate estimates of the ground-state energy of the two-dimensional fermionic Hubbard model.
authors.affiliation: Scuola Internazionale Superiore di Studi Avanzati and Democritos National Simulation Center, Istituto Officina dei Materiali del CNR, Via Bonomea 265, I-34136 Trieste, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Carleo
authors.forename: Federico
authors.initials: F
authors.lastname: Becca
authors.forename: Saverio
authors.initials: S
authors.lastname: Moroni
authors.forename: Stefano
authors.initials: S
authors.lastname: Baroni