Title: Emergent topological superconductivity at nematic domain wall of FeSe,
Abstract: One dimensional hybrid systems play an important role in the search for
topological superconductivity. Nevertheless, all one dimensional hybrid systems
so far have been externally defined. Here we show that one-dimensional domain
wall in a nematic superconductor can serve as an emergent hybrid system in the
presence of spin-orbit coupling. As a concrete setting we study the domain wall
between nematic domains in FeSe, which is well established to be a nematic
superconductor. We first show on the symmetry grounds that spin-triplet pairing
can be induced at the domain wall by constructing a Ginzburg-Landau theory. We
then demonstrate using Bogoliubov-de Gennes approach that such nematic domain
wall supports zero energy bound states which would satisfy Majorana condition.
Well-known existence of these domain walls at relatively high temperatures,
which can in principle be located and investigated with scanning tunneling
microscopy, presents new opportunities for a search for realization of Majorana
bound states.