Pressure influence on bound polarons in a strained wurtzite GaN/Al_xGa_（1_x）N heterojunction under an electric field

• Published in: Journal of semiconductors no. 5; pp. 5 - 11
• Main Author: 张敏 班士良
• Format: Journal Article
• Language: Chinese
• Published: 2010
• Subjects: 光学声子模; 斯塔克效应; 束缚极化子; 氮化镓; 电场; 电声子相互作用; 纤锌矿; 静水压力
• ISSN: 1674-4926

The binding energies of bound polarons near the interface of a strained wurtzite GaN/Al_xGa_（1-x）N het-erojunction are studied by using a modified LLP variational method and a simplified coherent potential approximation under hydrostatic pressure and an external electric field.Considering the biaxial strain due to lattice mismatch or epitaxial growth,the uniaxial strain effects and the influences of the electron-phonon interaction as well as impurity-phonon interaction including the effects of interface-optical phonon modes and half-space phonon modes,the binding energies as functions of pressure,the impurity position,areal electron density and the phonon effect on the Stark energy shift are investigated.The numerical result shows that the contributions from the interface optical phonon mode with higher frequency and the LO-like half space mode to the binding energy and the Stark energy shift are important and obviously increase with increasing hydrostatic pressure,whereas the interface optical phonon mode wi