Fermi arc reconstruction at junctions between Weyl semimetals

We analyze junctions between noninteracting fermionic topological phases. A closed-form condition for the existence of localized modes at the interface is derived using the transfer matrix approach. These analytical conditions as well as numerical exact diagonalization are used to study interfaces between Weyl semimetals. We observe a Fermi arc reconstruction at the interface, leading to curves of zero energy modes in the interface Brillouin zone. These are stable even in certain cases where the two Weyl semimetals differ only in their Fermi arc connectivities.