Extended Data Fig. 4: Microscope images of two microrings under test.

(a) one with the integrated mirror (that is, at an exceptional surface, ES) and (b) one without (that is, at a diabolic point, DP) as a traditional cavity-QED system.

(a) one with the integrated mirror (that is, at an exceptional surface, ES) and (b) one without (that is, at a diabolic point, DP) as a traditional cavity-QED system.