Single mode vertical cavity surface emitting laser using photonic crystals with a central defect

摘要

A vertical cavity surface emitting laser (VCSEL) using photonic crystals with a central defect. At least one of the mirror layers of a VCSEL includes a photonic crystal with a central defect. The central defect, which is surrounded by a periodic structure of holes or cavities, permits laser light to propagate and exit the VCSEL. Semi-insulating regions are formed in the active region such that when cavities are drilled in the photonic crystal and penetrate the active region, the cavities pass through the semi-insulating regions. This reduces the surface recombination that would otherwise occur in the active region and prevents the threshold current from increasing. The photonic crystal with a central defect has a reflectivity that is wavelength dependent. The VCSEL thus emits a single mode.