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Quasi-particle behavior of composite fermions in the half-filled Landau level

Peter Kopietz·Guillermo E. Castilla
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Abstract

We calculate the effect of infrared fluctuations of the Chern-Simons gauge field on the single-particle Green's function of composite fermions in the half-filled Landau level via higher-dimensional bosonization on a curved Fermi surface. We find that composite fermions remain well-defined quasi-particles, with an effective mass given by the mean-field value, but with anomalously large damping and a spectral function that contains considerable weight away from the quasi-particle peak.

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Peter Kopietz, Guillermo E. Castilla. 1996-12-09. Quasi-particle behavior of composite fermions in the half-filled Landau level. https://doi.org/10.1103/physrevlett.78.314

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