  The hallmark of topological crystalline insulators is the emergence of a
robust electronic state in a bandgap localized at the boundary of the material.
However, end, edge, and surface states can also have a non-topological origin.
Unfortunately, topological invariants such as the winding number and Zak-phase
are often not directly experimentally accessible for solids. In addition to
topological invariants, the position of the Wannier centers provide a
fingerprint for the topological character of a material. Here, we demonstrate a
method to experimentally determine the location of Wannier centers in
artificial lattices made of Cs/InAs(111)A by integrating the density of states.
We determine the locations of the Wannier centers for various 1D chains,
topological and trivial, and corroborate our findings with tight-binding
simulations.
