Single-fundamental-mode photonic-crystal vertical-cavity surface-emitting lasers

A photonic-crystal vertical-cavity surface-emitting laser (PC-VCSEL) is proposed and demonstrated. The 850-nm-PC-VCSEL shows single-mode continuous-wave operation in the entire current range. The side-mode suppression ratio is 35–40 dB for the sample with the hole pitch (Λ) 5 μm and the hole diameter (a) 3.5 μm. The guiding effect of the single-defect triangular-lattice two-dimensional photonic crystal structure is experimentally observed and is explained by the effective index model.