Origin of competing blue and green emission in InGaN/GaN quantum-disks in nanowires heterostructure

We report on the mechanism of emission quenching for InGaN/GaN quantum-disks in nanowires heterostructure grown catalyst-free using plasma-assisted molecular beam epitaxy. Temperature-dependent photoluminescence measurement shows the existence of blue and green emission spectra, with the blue peak quenched at room temperature. Characterization results suggest that the quenching is caused by the presence of stacking faults, strain, and the possibility of point defects in the active region.