Investigation of the efficiency-droop mechanism in a GaN based blue light-emitting diodes using a very-fast electrical-optical pump-probe technique

摘要

Electrical-optical pump-probe is used to investigate GaN blue LEDs under different temperatures. Measurement result indicates that under moderate current density (∼200A/cm2) piezoelectric field induced carrier-escaping cannot be neglected and is responsible for the observed efficiency-droop.