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Griffiths phase in the thermal quantum Hall effect

A. Mildenberger·F. Evers·R. Narayanan·A. D. Mirlin·K. Damle
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Abstract

Two dimensional disordered superconductors with broken spin-rotation and time-reversal invariance, e.g. with p_x+ip_y pairing, can exhibit plateaus in the thermal Hall coefficient (the thermal quantum Hall effect). Our numerical simulations show that the Hall insulating regions of the phase diagram can support a sub-phase where the quasiparticle density of states is divergent at zero energy, ρ(E)\sim |E|^{1/z-1}, with a non-universal exponent $z>1$, due to the effects of rare configurations of disorder (``Griffiths phase'').

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A. Mildenberger, F. Evers, R. Narayanan, A. D. Mirlin, K. Damle. 2005-03-29. Griffiths phase in the thermal quantum Hall effect. https://doi.org/10.1103/physrevb.73.121301

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