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arXiv · 1004.1806

Unconventional Fermi surface in two-dimensional systems of Dirac fermions

Jing-Rong Wang·Guo-Zhu Liu
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Abstract

At the low energy regime, the decay rate of two-dimensional massless Dirac fermions due to interactions can be written as $\mathrm{Im}Σ(ω) \propto |ω|^{x}$ at zero temperature. We find that the fermion system has: I) no sharp Fermi surface and no well-defined quasiparticle peak for $0 1$. In the presence of long-range gauge/Coulomb interaction or certain massless boson mode, the system exhibits unusual behavior belonging to class II.

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Jing-Rong Wang, Guo-Zhu Liu. 2010-04-11. Unconventional Fermi surface in two-dimensional systems of Dirac fermions. https://arxiv.org/abs/1004.1806

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