Coupling in a dual metallo-dielectric nanolaser system.

To achieve high packing density in on-chip photonic integrated circuits, subwavelength scale nanolasers that can operate without crosstalk are essential components. Metallo-dielectric nanolasers are especially suited for this type of dense integration due to their lower Joule loss and nanoscale dimensions. Although coupling between optical cavities when placed in proximity to one another has been widely reported, whether the phenomenon is induced for metal-clad cavities has not been investigated thus far. We demonstrate coupling between two metallo-dielectric nanolasers by reducing the separation between the two cavities. A split in the resonant wavelength and quality factor is observed, caused by the creation of bonding and anti-bonding supermodes. To preserve the independence of the two closely spaced cavities, the resonance of one of the cavities is detuned relative to the other, thereby preventing coupling.