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arXiv · 1003.5299

Dynamical chiral symmetry breaking in QED$_{3}$ at finite density and impurity potential

Wei Li·Guo-Zhu Liu
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Abstract

We study the effects of finite chemical potential and impurity scattering on dynamical fermion mass generation in (2+1)-dimensional quantum electrodynamics. In any realistic systems, these effects usually can not be neglected. The longitudinal component of gauge field develops a finite static length produced by chemical potential and impurity scattering, while the transverse component remains long-ranged because of the gauge invariance. Another important consequence of impurity scattering is that the fermions have a finite damping rate, which reduces their lifetime staying in a definite quantum state. By solving the Dyson-Schwinger equation for fermion mass function, it is found that these effects lead to strong suppression of the critical fermion flavor $N_c$ and the dynamical fermion mass in the symmetry broken phase.

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Wei Li, Guo-Zhu Liu. 2010-03-27. Dynamical chiral symmetry breaking in QED$_{3}$ at finite density and impurity potential. https://doi.org/10.1103/physrevd.81.045006

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