A new class of (2+1)-dimensional topological superconductors with Z8 topological classification

The classification of topological states of matter depends on spatial dimension and symmetry class. For non-interacting topological insulators and superconductors, the topological classification is obtained systematically and non-trivial topological insulators are classified by either integer or Z(2). The classification of interacting topological states of matter is much more complicated and only special cases are understood. In this paper we study a new class of topological superconductors in (2 + 1) dimensions which has time-reversal symmetry and a Z(2) spin conservation symmetry. We demonstrate that the superconductors in this class are classified by Z(8) when electron interaction is considered, while the classification is Z without interaction.