Griffiths phase in the thermal quantum Hall effect

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, rho(E)similar to parallel to E parallel to(1/z-1), with a nonuniversal exponent z > 1, due to the effects of rare configurations of disorder (Griffiths phase).