Topological quantum photonics

Topological quantum photonics explores the interaction of the topology of the dispersion relation of photonic materials with the quantum properties of light. The main focus of this field is to create robust photonic quantum information systems by leveraging topological protection to produce and manipulate quantum states of light that are resilient to fabrication imperfections and other defects. In this perspective, we provide a theoretical background on topological protection of photonic quantum information and highlight the key state-of-the-art experimental demonstrations in the field, categorizing them based on the quantum features they address. An analysis of the key challenges and limitations concerning topological protection of quantum states is presented. Importantly, this paper takes a thorough perspective look into what future research in this area may bring.