ABSTRACT

The concept of a superluminescent light-emitting diode (SLED) was proposed for the first time. It can be briefly described as an edge-emitting semiconductor light source that operates in the so-called superluminescence regime, also known as the amplified spontaneous emission (ASE) regime. SLEDs are realized as epitaxially grown layers on a substrate in an index-guided ridge-waveguide geometry similar to Fabry–Perot-type laser diodes. A couple of different approaches exist for the modeling and simulation of SLEDs. An SLED device is assumed with a perfect front facet having zero residual reflection, similar to an ideal standard SLED, but with a back facet being a perfect reflector that reflects all incident light back into the waveguide. Commercial SLEDs have to fulfill target specifications for the electro-optical performance that are defined by the application. Generally, all approaches for the design of SLED structures showing an ASE spectrum with ultrawide emission bandwidth are based on a multitransition design.