Phys.
Rev. B 65, 012506 (2002) (4 pages)
(Received 5 July 2001; published 4 December 2001)
We
study the symmetry class for localization which arises from models
of noninteracting quasiparticles in disordered superconductors that
have neither time-reversal nor spin-rotation invariance. Two-dimensional
systems in this category, which is known as class D, can display
phases with three different types of quasiparticle dynamics:
metallic, localized, or with a quantized (thermal) Hall conductance.
Correspondingly, they can show a variety of delocalization transitions.
We illustrate this behavior by investigating numerically the phase
diagrams of network models with the appropriate symmetry and show
the appearance of the metallic phase.
©2001
The American Physical Society