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

• Published in: Physica. E, Low-dimensional systems & nanostructures Low-dimensional systems & nanostructures, 2016-02, Vol.76, p.164-168
• Main Authors: Huang, Wen Deng, Chen, Guang De, Yuan, Zhao Lin, Yang, Chuang Hua, Ye, Hong Gang, Wu, Ye Long
• Format: Article
• Language: English
• Subjects: 63.20.D- –Phonon; 63.20.kd –Electron- phonon interaction; 73.21.La –Quantum dot; Electron–phonon interaction; Phonon mode; Quantum dot
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2015.10.017

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. 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 in high frequency region, the interface optical phonon frequencies appear linear change. In low frequency region, the frequencies appear non-linear change. [Display omitted] •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.