Topological photonic nanocavity provides a robust platform for realizing nano-photonic devices and studying light–matter interaction. Here, a topological photonic-plasmonic hybrid nanocavity, assembling a topological photonic crystal (PhC) nanocavity with a plasmonic nano-antenna, is proposed to have an ultra-high figure of merit Q/V of , which is two orders higher than that of the bare topological PhC nanocavity. The single-atom cooperativity parameter is improved by over 60 times due to the large enhancement of Q/V, which makes the coupling between light and a single emitter enter a strong coupling region in topological photonic realm for the first time. Meanwhile, strong coupling and weak coupling can be easily switched in the topological hybrid system by tuning the structure dimension of plasmonic nano-antennas. This work provides a robust platform to control coupling phase transition between light and a single emitter, which has great potential in topological lasers, quantum optics and quantum information.

拓扑光子纳米腔为实现纳米光子器件和研究光-物质相互作用提供了一个强大的平台。这里，拓扑光子电浆混合纳腔，组装与等离子体激元纳米天线拓扑光子晶体（PHC）纳腔，提出了具有优点的超高数字Q / V的，其比的高两个数量级裸拓扑PhC纳米腔。Q / V大幅提升，单原子协同参数提升60倍以上，这使得光与单个发射器之间的耦合首次进入拓扑光子领域的强耦合区域。同时，通过调整等离子体纳米天线的结构尺寸，可以在拓扑混合系统中轻松切换强耦合和弱耦合。这项工作提供了一个强大的平台来控制光和单个发射器之间的耦合相变，这在拓扑激光器、量子光学和量子信息方面具有巨大的潜力。