The crucial role of InAlN for blue and green LDs and SLEDs with low power consumption

An n-type InAlN cladding design based on multiple GaN/InAlN pairs is successfully implemented in edge-emitting laser diodes (LDs) and superluminescent light emitting diodes (SLEDs) emitting in the blue and green spectral range. Thanks to the stronger refractive index contrast with respect to waveguiding layers enabled by this approach, larger optical confinement factors are obtained. The resulting larger modal gains translate into remarkable performance improvements for LD and SLEDs with respect to conventional AlGaN based claddings. LDs with threshold currents as low as 3 mA in the blue and 12 mA in the green spectral range are demonstrated. Similarly, an operating current decrease of >100 mA is reported for state-of-the-art green SLEDs.