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A discrete Hubbard-Stratonovich decomposition for general, fermionic two-body interactions

S. Rombouts·K. Heyde·N. Jachowicz
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Abstract

A scheme is presented to decompose the exponential of a two-body operator in a discrete sum over exponentials of one-body operators. This discrete decomposition can be used instead of the Hubbard-Stratonovich transformation in auxiliary-field quantum Monte-Carlo methods. As an illustration, the decomposition is applied to the Hubbard model, where it is equivalent to the discrete Hubbard-Stratonovich transformation introduced by Hirsch, and to the nuclear pairing Hamiltonian.

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S. Rombouts, K. Heyde, N. Jachowicz. 1998-04-27. A discrete Hubbard-Stratonovich decomposition for general, fermionic two-body interactions. https://doi.org/10.1016/s0375-9601(98)00197-2

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