Cyan Superluminescent Light-Emitting Diode Based on InGaN Quantum Wells

An InGaN superluminescent light-emitting diode (SLED) with emission as long as 500 nm is presented. Up to now, an SLED with such a long wavelength was hindered, because the gain of indium-rich layers was not sufficient for operating in superluminescence mode. We used an epitaxial structure with high material gain as well as a special chip design of curved waveguide to solve this problem. The SLED reached an output power of >4 mW with a spectral bandwidth of 4.4 nm driven in pulsed mode.