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arXiv · 0906.1103

A Criterion for the Critical Number of Fermions and Chiral Symmetry Breaking in Anisotropic QED(2+1)

A. Concha·V. Stanev·Z. Tesanovic
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Abstract

By analyzing the strength of a photon-fermion coupling using basic scattering processes we calculate the effect of a velocity anisotropy on the critical number of fermions at which mass is dynamically generated in planar QED. This gives a quantitative criterion which can be used to locate a quantum critical point at which fermions are gapped and confined out of the physical spectrum in a phase diagram of various condensed matter systems. We also discuss the mechanism of relativity restoration within the symmetric, quantum-critical phase of the theory.

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A. Concha, V. Stanev, Z. Tesanovic. 2009-06-05. A Criterion for the Critical Number of Fermions and Chiral Symmetry Breaking in Anisotropic QED(2+1). https://doi.org/10.1103/physrevb.79.214525

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