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Delocalization of 2D Dirac Fermions: the Role of a Broken Supersymmetry

K. Ziegler
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Abstract

The mechanism of delocalization of two-dimensional Dirac fermions with random mass is investigated, using a superfield representation. Although localization effects are very strong, one fermion component can delocalize due to the spontaneous breaking of a special supersymmetry of the model. The delocalized fermion has a non-singular density of states and is decribed by a diffusion propagator. Supersymmetry is restored if the mean of the random mass is sufficiently large. This is accompanied by a critical boson component.

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K. Ziegler. 1997-11-11. Delocalization of 2D Dirac Fermions: the Role of a Broken Supersymmetry. https://doi.org/10.1103/physrevlett.80.3113

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