A topological quantum optics interface*

Topological photonics have opened up a multitude of new avenues in designing photonic devices. While exotic physics has been explored with topological photonic states in classical domain, strong light matter interaction with topological photonic states in the quantum regime remains largely unexplored. Towards this goal, we fabricate a topological photonic crystal to mediate coupling between single quantum emitter and topological photonic states. Developed on a thin slab of Gallium Arsenide membrane with electron beam lithography, such a device supports two robust counter-propagating edge states at the boundary of two distinct topological photonic crystals at near-IR wavelength. We show chiral coupling of circularly polarized lights emitted from a single Indium Arsenide quantum dot under strong magnetic field into these topological edge modes and demonstrate their robustness against sharp bends. Our technique could open up opportunities to explore many-body interaction, fault-tolerant photonic circuits and unconventional quantum states of light.