Highly efficient superluminescent light-emitting diodes (SLEDs) at 625–650 nm

Superluminescent light-emitting diodes (SLEDs) are very attractive as compact, highly efficient light sources for various applications in the visible red spectral region. We simulate and discuss the electro-optical performance of SLEDs operating at center wavelengths of 625-650 nm. We show that for current SLED structures the optimum wavelength with respect to maximum luminous flux and power conversion efficiency is around 635 nm. Design improvements of the epitaxial layer structure offer the way to shorter wavelengths with higher luminous flux and efficiency values.