Abstract

We give an overview of the Gaussian phase-space methods for fermions, focusing on the example of the Hubbard model, which describes ultracold fermions in a lattice. The phase-space methods do not suffer the sort of sign problem encountered by other quantum Monte Carlo methods, and provide an efficient means of calculating exact zero-temperature Hubbard results. However at finite temperature, there are known issues to do with the boundedness of the underlying distribution. We show how ‘stochastic gauges’ can be used to control the distribution tails and thereby improve the accuracy of the simulations at low temperatures.

© 2007 Optical Society of America