It is shown theoretically that a one-dimensional crystal with time-reversal and particle-hole symmetries is characterized by a topological invariant that predicts the existence or otherwise of edge states. This is confirmed experimentally through the construction and simulation of a photonic crystal analog in the microwave regime. It is shown that the edge mode couples to modes external to the pho... read moretonic crystal via a Fano resonance.read less
T. J. Atherton, C. A. M. Butler, M. C. Taylor, I. R. Hooper, A. P. Hibbins, J. R. Sambles and H. Mathur, Physical Review B - Condensed Matter and Materials Physics 93 (12) (2016). https://doi.org/10.1103/PhysRevB.93.125106.