Ternary mixed crystal effects on interface optical phonon and electron-phonon coupling in zinc-blende GaN/AlxGa1−xN spherical quantum dots

•The random-element isodisplacement model and dielectric continuum model are used.•The Al component on IO phonon dispersions are studied.•The Al component on electron–IO coupling strengths are studied.

The theoretical investigations of the interface optical phonons, electron–phonon couplings and its ternary mixed effects in zinc-blende spherical quantum dots are obtained by using the dielectric continuum model and modified random-element isodisplacement model. The features of dispersion curves, electron–phonon coupling strengths, and its ternary mixed effects for interface optical phonons in a single zinc-blende GaN/AlxGa1−xN spherical quantum dot are calculated and discussed in detail. The numerical results show that there are three branches of interface optical phonons. One branch exists in low frequency region; another two branches exist in high frequency region. The interface optical phonons with small quantum number l have more important contributions to the electron–phonon interactions. It is also found that ternary mixed effects have important influences on the interface optical phonon properties in a single zinc-blende GaN/AlxGa1−xN quantum dot. With the increase of Al component, the interface optical phonon frequencies appear linear changes, and the electron–phonon coupling strengths appear non-linear changes in high frequency region. But in low frequency region, the frequencies appear non-linear changes, and the electron–phonon coupling strengths appear linear changes.

Graphical abstractTernary mixed effects have important influences on the interface optical phonon properties in a single zinc-blende GaN/AlxGa1−xN quantum dot. With the increase of Al component in high frequency region, the interface optical phonon frequencies appear linear change. In low frequency region, the frequencies appear non-linear change.Figure optionsDownload full-size imageDownload as PowerPoint slide