Lawrence, Felix J.Botten, LindsayDossou, Kokou BMcPhedran, Rossde Sterke, C Martijn2015-12-101050-2947http://hdl.handle.net/1885/56864We present a method for finding surface modes at interfaces between two-dimensional photonic crystals (PCs), in which the surface modes are represented as superpositions of the PCs' propagating and evanescent Bloch modes. We derive an existence conditionKeywords: Band edge; Band gaps; Bloch modes; Existence conditions; Impedance matrices; PC interfaces; Surface modes; Three-layer structures; Two-dimensional photonic crystals; Waveguide mode; Crystallography; Microcomputers; Photonic crystals; Waveguides; Two dimen201010.1103/PhysRevA.82.0538402016-02-24