Optical control of the quality factor using coupled photonic crystal cavities

We have demonstrated optical control of quality-factor (Q-factor) using coupled photonic crystal cavities. A double heterostructure (DHS) cavity has been thermo-optically brought in resonance to an adjacent Febry-Pérot cavity to reduce the optical confinement and hence decrease the Q-factor. Both the strong and weak coupling phenomena between two cavities have been studied. Up to 50% Q-factor change has been experimentally observed. The corresponding modification of the local density of states enables the control of the spontaneous emission rate of the quantum emitters in the DHS cavity.