New high-power single-mode superluminescent diode with low spectral modulation

Summary form only given. The requirements of high-power and single-waveguide-mode impose conflicting constraints on superluminescent diode (SLD) active stripe design. A solution to this problem is provided by adiabatic tapers. However, due to the large stripe width at the facet, such designs do not lead to efficient single-mode fiber coupling, particularly at both ends of the device. We have solved this problem by designing the active stripe of an angled stripe SLD in the shape of a "diamond", which performs as an adiabatic expander followed by an adiabatic "contractor" to provide a single-mode optical field at the facet with a size that is compatible with lens and fiber coupling.