ABC-model for interpretation of internal quantum efficiency and its droop in III-nitride LEDs: a review

The paper reviews applications of ABC-model to interpret internal quantum efficiency and its droop in III-nitride light-emitting diodes. Advantages of the model, its intrinsic limitations, and tentative mechanisms responsible for deviation of the model predictions from available observations are discussed. New experimental information on recombination processes in the LED active regions coming in terms of the ABC-model is considered along with still open questions and tasks for further experimental and theoretical studies.