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arXiv · 1103.3730

From Popov-Fedotov trick to universal fermionization

Nikolay Prokof'ev·Boris Svistunov
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Abstract

We show that Popov-Fedotov trick of mapping spin-1/2 lattice systems on two-component fermions with imaginary chemical potential readily generalizes to bosons with a fixed (but not limited) maximal site occupation number, as well as to fermionic Hamiltonians with various constraints on the site Fock states. In a general case, the mapping---fermionization---is on multi-component fermions with many-body non-Hermitian interactions. Additionally, the fermionization approach allows one to convert large many-body couplings into single-particle energies, rendering the diagrammatic series free of large expansion parameters; the latter is essential for the efficiency and convergence of the diagrammatic Monte Carlo method.

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Nikolay Prokof'ev, Boris Svistunov. 2011-07-01. From Popov-Fedotov trick to universal fermionization. https://doi.org/10.1103/physrevb.84.073102

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