Single atom edge-like states via quantum interference
  We demonstrate how quantum interference may lead to the appearance of robust edge-like states of a single ultracold atom in a two-dimensional optical ribbon. We show that these states can be engineered either within the manifold of local ground states of the sites forming the ribbon, or of states carrying one unit of angular momentum. In the former case, we show that the implementation of edge-like states can be extended to other geometries, such as tilted square lattices. In the latter case, we suggest to use the winding number associated to the angular momentum as a synthetic dimension. 
G. Pelegr\'i, J.Polo, A. Turpin, M. Lewenstein, J. Mompart, and V.   Ahufinger
quant-ph