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arXiv · 1003.3696

Reptation quantum Monte Carlo for lattice Hamiltonians with a directed-update scheme

Giuseppe Carleo·Federico Becca·Saverio Moroni·Stefano Baroni
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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-states 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.

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Giuseppe Carleo, Federico Becca, Saverio Moroni, Stefano Baroni. 2010-03-19. Reptation quantum Monte Carlo for lattice Hamiltonians with a directed-update scheme. https://doi.org/10.1103/physreve.82.046710

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