  We consider a Su-Schrieffer-Heeger chain to which we attach a semi-infinite
undimerized chain (lead) to both ends. We study the effect of the openness of
the SSH model on its properties. A representation of the infinite system using
an effective Hamiltonian allows us to examine its low-energy states in more
detail. We show that, as one would expect, the topological edge states
hybridize as the coupling between the systems is increased. As this coupling
grows, these states are suppressed, while a new type of edge state emerges from
the trivial topological phase. These new states, referred to as phase-inverted
edge states, are localized low-energy modes very similar to the edge states of
the topological phase. Interestingly, localization occurs on a new shifted
interface, moving from the first (and last) site to the second (and second to
last) site. This suggests that the topology of the system is strongly affected
by the leads, with three regimes of behavior. For very small coupling the
system is in a well-defined topological phase; for very large coupling it is in
the opposite phase; in the intermediate region, the system is in a transition
regime.
