Quasi-topological phases of matter and topological protection

摘要: We discuss systems which have some, but not all of the hallmarks topological phases. These systems' character is fully captured by a local order parameter, they are also described at low energies quantum field theories. For such systems, we formulate concepts quasi-topological phases (to be contrasted with true phases), and symmetry-protected describe examples in each class implications for protection information operations. explain why greater stability than sometimes appreciated. In that discuss, focus on Ising-type (a.k.a. Majorana) particularly relevant to recent theoretical advances experimental efforts.