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Quantum Monte Carlo simulation in the canonical ensemble at finite temperature

Kris Van Houcke·Stefan Rombouts·Lode Pollet
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Abstract

A quantum Monte Carlo method with non-local update scheme is presented. The method is based on a path-integral decomposition and a worm operator which is local in imaginary time. It generates states with a fixed number of particles and respects other exact symmetries. Observables like the equal-time Green's function can be evaluated in an efficient way. To demonstrate the versatility of the method, results for the one-dimensional Bose-Hubbard model and a nuclear pairing model are presented. Within the context of the Bose-Hubbard model the efficiency of the algorithm is discussed.

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Kris Van Houcke, Stefan Rombouts, Lode Pollet. 2006-01-31. Quantum Monte Carlo simulation in the canonical ensemble at finite temperature. https://doi.org/10.1103/physreve.73.056703

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