Calculation of optical transition energies for self-formed InGaN quantum dots

The energy levels determining optical transitions within indium-rich InGaN quantum dots are estimated by calculating ground state energy levels in the regime of strong 3D confinement. Effects due to finite barrier heights and variation in band offset ratios are included and the consequences of the strong piezoelectric fields within the dots considered. It is shown that the lowest optical transitions in spherical quantum dots with radii up to 10 nm correspond to wavelengths covering the visible spectrum. These results are discussed in relation to the significant recent advances in light emitters based on InGaN layers.