I V Akimova

Recombination balance in green-light-emitting GaN/InGaN/AlGaN quantum wells

Recombination balance parameters for GaN/InGaN/AlGaN single-quantum-well green-lightemitting diodes are extracted from optical power and carrier lifetime measurements. The radiative recombination coefficient B is found to depend on two-dimensional carrier density N, with a low-carrier-density limit of B0=1.2×10−4 cm2/s. Sublinearity of the light–current characteristic at temperatures ⩾300 K is associated with a nonradiative process whose rate is proportional to ∼N4.8. The external quantum efficiency of 5.5% at 20 mA results from the internal quantum yield of 63% and the photon extraction efficiency of 8.7%. At low temperatures, a nonradiative loss term proportional to ∼N9 is also identified.