Studies On Plasmon Characteristics In Semiconductor Single Quantum Wells

GaN materials is the new semiconductor materials in development of microelectronic devices, optoelectronic devices. Research and Application of GaN materials is currently the world's semiconductor research frontier and hot. As we all know, the elementary excitations are the important theoretical basis to reveal the nature of electron-electron interaction. Therefore, the research on the properties of elementary excitations of GaN material is very important.In the thesis, using the model of the single quantum well, taking into account of the polarization effect of AlxGa1-xN-GaN interface, applying self-consistent solution, we obtain the wave function and the self-energy of the system.Based on random phase approximation (RPA) framework, we have derived dielectric function in eigenvector space with single-particle Hamiltonian. And then, we derived the dielectric function tensor in both the two sub-band model and the three sub-band model. In the end, we got the equation of the single-particle excitation.Obtained formula by the theoretical, we studied the property of collective excitations of the system in both the second sub-band model and the three sub-band model. Each excitation mode is given the energy depending on the wave vector. Finally, we compared the results of the two sub-band model and the three sub-band model in study of the system.