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Physical review. B, Condensed matter

Monte Carlo calculations of coupled boson-fermion systems. II

Douglas J. Scalapino, Robert L. Sugar

Published Oct 15, 1981• 110 citations
Publisher

Abstract

We have recently developed a formalism for carrying out Monte Carlo calculations on systems with coupled boson-fermion degrees of freedom. Here we present the results obtained using these techniques on some specific systems. First the quantum-mechanics problem of a single boson coordinate linearly coupled to a fermion is studied. The fermion Green's function and the boson coordinate displacement are calculated and compared with exact results. Extending this analysis to a one-dimensional array, a field theory in one space and one imaginary time dimension is investigated. The fermion and boson Green's functions are calculated and compared with analytic results obtained in the limit where the bare boson frequency is much larger or much smaller than the characteristic fermion energies.

DOI
10.1103/physrevb.24.4295

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