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