Quantum Topological Photonics

Abstract Quantum topological photonics is a new research field with great potential that is based on developments in both quantum optics and topological photonics. Topological photonics offers unique properties, including topological robustness and an anti‐backscattering property, and these advantages are strongly required in quantum optics. Quantum technology, which includes quantum optics, represents an important direction for future technological development. However, existing quantum light sources are unstable and quantum information may easily be lost during transmission. These disadvantages have troubled researchers for a long time and no perfect solution is available thus far. Fortunately, application of topological photonics to quantum optics can help to generate robust quantum light sources and protect photons from decoherence during photon propagation. This allows the correlation and entanglement to be maintained even when photons travel over long distances. To date, quantum topological photonics has provided major breakthroughs in certain quantum devices. This Review presents the basic concepts of quantum topological photonics and summarizes how the topological protection property works in quantum light sources, quantum information transmission, and other quantum devices. Finally, an outlook is provided on the remaining challenges and potential future directions of quantum topological photonics, which can aid in exploration of additional new phenomena.