Piezoelectric field, exciton lifetime, and cathodoluminescence intensity at threading dislocations in GaN{0001}

Abstract

The strain field of a dislocation emerging at a free surface is partially relaxed to ensure stress free boundary conditions. We show that this relaxation strain at the outcrop of edge threading dislocations in GaN{0001} gives rise to a piezoelectric volume charge. The electric field produced by this charge distribution is strong enough to dissociate free excitons at distances over 100 nm from the dislocation line. We evaluate the impact of this effect on cathodoluminescence images of dislocations.

References in corpus (4)

• Atomistic determination of flexoelectric properties of crystalline dielectrics
• First-principles theory and calculation of flexoelectricity
• Interrelation of structural and electronic properties of InGaN/GaN quantum dots using an eight-band k.p model
• Dislocation contrast in cathodoluminescence and electron-beam induced current maps on GaN(0001)

Cited by in corpus (4)

• Carrier diffusion in GaN -- a cathodoluminescence study. III: Nature of nonradiative recombination at threading dislocations
• Determination of the carrier diffusion length in GaN from cathodoluminescence maps around threading dislocations: fallacies and opportunities
• Carrier diffusion in GaN -- a cathodoluminescence study. II: Ambipolar vs. exciton diffusion
• Dislocation correlations in GaN epitaxial films revealed by EBSD and XRD