Abstract

Internal quantum efficiency of radiation (IQE) for the near-band-edge (NBE) emission of freestanding-GaN crystals was observed by omnidirectional photoluminescence spectroscopy at various temperatures between 12 K and 300 K. A photoluminescence quenching ratio (Rq), defined by a spectrally integrated NBE emission obtained at 300 K to that obtained at 12 K, showed a lower value (2%) comparing with the IQE value (5.5%) for the GaN with the free electron concentration of 1 × 1017 cm−3 under cw photo-pumping density of 13 W cm−2. This difference arises from the nonlinear relationship between IQE and the external quantum efficiency owing to the photon recycling effect.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call