Topological properties arising from quantum mechanical nature of electron wave functions in solids are a source of many interesting and unexpected phenomena in phases of matter that are robust against deformations/perturbations.They have been playing a key role in physics of the quantum Hall effect, and, more recently, time-reversal symmetric topological insulators in two and three dimensions.
Topological superconductors, close cousins of topological insulators, are fully gapped in the bulk but have gapless surface Andreev bound states because of non-trivial topological properties of bulk wave functions of Bogoliubov quasi-particles. Since its theoretical proposal, it has been a challenge to discover an experimental realization of a topological superconductor in three dimensions.
For example, a cupper doped topological insulator (bismuth selenide) has been speculated to be a topological superconductor below around 4K.
In this talk, I will discuss various aspect of topological superconductors and related systems.In particular, I will present a response theory of topological superconductors.It closely parallels the topological magnetoelectric effect in three dimensional topological superconductors, and reveals an unexpected connection between thermal and mechanical responses in topological superconductors.