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Dynamical Generation of Fermion Mass and Magnetic Field in Three-Dimensional QED with Chern-Simons Term

Taichi Itoh·Hiroshi Kato
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Abstract

We study dynamical symmetry breaking in three-dimensional QED with a Chern-Simons (CS) term, considering the screening effect of $N$ flavor fermions. We find a new phase of the vacuum, in which both the fermion mass and a magnetic field are dynamically generated, when the coefficient of the CS term $κ$ equals $N e^2/4 π$. The resultant vacuum becomes the finite-density state half-filled by fermions. For $κ=N e^2/2 π$, we find the fermion remains massless and only the magnetic field is induced. For $κ=0$, spontaneous magnetization does not occur and should be regarded as an external field.

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Taichi Itoh, Hiroshi Kato. 1998-06-08. Dynamical Generation of Fermion Mass and Magnetic Field in Three-Dimensional QED with Chern-Simons Term. https://doi.org/10.1103/physrevlett.81.30

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