Fig. 1: Coupled PT-symmetric microresonators system and the concept of configurable photon lifetime.
From: Quantum light sources with configurable lifetime leveraging parity-time symmetry
a Sketch of the coupled dual-ring system. The main ring (red) with a radius of \({R}_{1}\) is coupled to the auxiliary ring (blue) with a radius of \({R}_{2}\). The intrinsic decay of the main and auxiliary ring is \({\gamma }_{1}\) and \({\gamma }_{2}\), respectively. The coupling strength between two rings is \(\kappa\). The thermal tuning module is fabricated upon the auxiliary ring. The auxiliary ring is coupled to the bus waveguide with the coupling decay rate \({\gamma }_{{{{\rm{c}}}}}\). Photon pairs are generated via the spontaneous four wave-mixing (SFWM) that occurs in the main ring. b Normalized intracavity photon density of state (DOS) of the main ring, with yellow arrows indicating the thermal tuning of the resonance of the auxiliary ring (redshift in wavelength axis). c Photon DOS evolutions (i) without (w/o) and (ii) with (w/) PT-symmetry. d Detailed DOS of photon at different detuning statuses marked by the dashed lines in c (ii).
