Double-Disk Structure for Output Coupling in Microdisk Lasers

We report our experiment on the use of a double-disk structure to couple light output from a microdisk laser which allows us to maintain a high Q value of the microdisk resonator. The small photon leakage rate from the lower lasing disk to the top waveguiding disk can be carefully controlled by choosing the distance between the two disks. Various structures can be fabricated on the top disk to couple the light out. In this letter, a simple opening in the top disk is used for output coupling.