Effects of Wavelength and Defect Density on the Efficiency of (In,Ga)N-Based Light-Emitting Diodes

The efficiency of (In,Ga)N light-emitting diodes decreases from blue to green---the so-called ``green gap'', which thwarts the engineering of white-light LED modules. While there is a fundamental limit due to increasing internal fields, the authors discover that increasing losses at defects are similarly important. This shifts the focus for improving solid-state lightning to optimizing growth conditions during the manufacture of green LEDs.