Folded Cavity Surface Emitting Lasers Fabricated by Focused Ion Beam Etching

Abstract

The development of compact and efficient laser sources at 1500nm and 1300nm without the need for cleaved edges has been pursued since the early 1980s with the development of vertical cavity surface emitting lasers (VCSELs). These lasers have been widely used for data communications, and are currently applied for high frequency optical interconnects. In the past, much work has been done to define higher power and higher frequency VCSELs. Lithographically defined photonic crystal lasers and annular Bragg reflector lasers have been recently developed within InGaAsP gain material emitting in the telecommunications spectrum. These geometries permitted the reduction of the mode volume to a minimum, but typically suffer from low gain and correspondingly small output power capability. Here, we explore the use of folded cavity lasers to obtain devices that combine large output power with efficient surface emission without the requirement of cleaving short cavities.