Diode lasers with cylindrical mirror facets and reduced beam divergence

Abstract
Using chemical etching and mass transport, we have monolithically integrated cylindrical lenses at one of the ends of buried-heterostructure GaInAsP/InP diode laser cavities. The lenses are designed to provide reflective feedback for low-threshold current (as low as 25 mA), as well as reduction of beam width in the lateral direction (as small as 9.2°).