Speaker
Annica Black-Schaffer
Description
Depositing magnetic impurities or islands on top of spin-orbit
coupled superconductors can generate a topological
superconducting state. For one-dimensional impurity wires, a
non-trivial topology will give rise to Majorana fermions
appearing at the end points of the wire, whereas for magnetic
islands edge states disperse across the bulk energy gap.
In this talk I will focus on several recent results for these
systems. I will show that persistent currents are generated
around magnetic impurities. The currents are independent on
topology, but still generally peak around the topological phase
transition. I will also show how a self-consistent solution for
the superconducting state results in a heavily suppressed
superconducting order parameter at the impurity sites, which
can even experience a pi-shift. This pi-shift can be explained
by impurity-induced quasiparticles being completely out of
phase with the condensate.
