One-dimensional Topological Superconductors: A double feature

I will review the recent developments in understanding and realizing
artificial topological superconductors (TSC) in one spatial dimension.
If time-reversal symmetry is broken, a TSC phase with unpaired
Majorana zero modes can be realized. I will discuss a unique signature
of this phase in spin-resolved current correlations, that
distinguishes it from an ordinary Andreev bound state. Even in the
absence of a magnetic field, time reversal invariant topological
superconducting (TRITOPS) phases are possible in 1D, in which a
Kramers pair of Majorana zero modes appears at each end. I will
outline the conditions the realization of such states and some
phenomena associated with them.