Thermal metal-insulator transition in a helical topological superconductor

Abstract

Two-dimensional superconductors with time-reversal symmetry have a Z 2 topological invariant, which distinguishes phases with and without helical Majorana edge states. We study the topological phase transition in a class-DIII network model and show that it is associated with a metal-insulator transition for the thermal conductance of the helical superconductor. The localization length diverges at the transition with critical exponent ν≈2.0, about twice the known value in a chiral superconductor. © 2012 American Physical Society.