Coherent coupling of two-dimensional arrays of defect cavities in photonic crystal vertical cavity surface-emitting lasers

An approach for creating two-dimensional arrays of coherently coupled vertically emitting laser cavities is demonstrated. This is achieved by creating a 2×2 array of defect cavities within the top distributed Bragg reflector of a photonic crystal vertical cavity surface-emitting laser. The optical coupling occurs laterally through coupling regions defined between the defect cavities. Modifying the index within the coupling regions, accomplished by varying the hole parameters of the photonic crystal in those regions, leads to out-of-phase coherent coupling observed in the far field. Agreement is found between the simulated and observed out-of-phase far fields.