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arXiv · 1605.01911

Critical behaviour of ($2+1$)-dimensional QED: 1/N_f-corrections in the Landau gauge

A. V. Kotikov·V. I. Shilin·S. Teber
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Abstract

The dynamical generation of a fermion mass is studied within ($2+1$)-dimensional QED with $N$ four-component fermions in the leading and next-to-leading orders of the 1/N expansion. The analysis is carried out in the Landau gauge which is supposed to insure the gauge independence of the critical fermion flavour number, N_c. It is found that the dynamical fermion mass appears for N<N_c where N_c=3.29, that is only about $1\%$ larger than its value at leading order.

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A. V. Kotikov, V. I. Shilin, S. Teber. 2016-05-06. Critical behaviour of ($2+1$)-dimensional QED: 1/N_f-corrections in the Landau gauge. https://doi.org/10.1103/physrevd.94.056009

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