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Gaussian operator bases for correlated fermions

J. F. Corney·P. D. Drummond
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Abstract

We formulate a general multi-mode Gaussian operator basis for fermions, to enable a positive phase-space representation of correlated Fermi states. The Gaussian basis extends existing bosonic phase-space methods to Fermi systems and thus enables first-principles dynamical or equilibrium calculations in quantum many-body Fermi systems. We prove the completeness and positivity of the basis, and derive differential forms for products with one- and two-body operators. Because the basis satisfies fermionic superselection rules, the resulting phase space involves only c-numbers, without requiring anti-commuting Grassmann variables.

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J. F. Corney, P. D. Drummond. 2005-11-02. Gaussian operator bases for correlated fermions. https://doi.org/10.1088/0305-4470/39/2/001

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