Résumé
Topological excitations in photonic crystals and metamaterials can be observed in many different guises. While passive periodic structures can support essentially topological Bloch modes, the insertion of quantum degrees of freedom can lead to a wealth of topological solutions such as solitons and vortices. We will present a survey of recent results in the field and try to describe the transition between trivial and non-trivial phases by studying the phase space of these structures.