Electronic Structure and Optical Properties of Zinc Oxide: Bulk and Surface
Abstract
To understand and describe optical phenomena microscopically has always been an interesting challenge in theoretical physics. This thesis contributes a full-band-structure calculation of the frequency-dependent dielectric and second harmonic response functions of ZnO. These functions characterize certain optical properties of the material and they are related to the microscopic structure of the material. In our calculation for ZnO, we use a linear combination of atomic orbitals (LCAO) technique to obtain the electronic energy band structure and wave functions semiempirically. In order to include the surface contributions to the optical properties of ZnO, we proposed a "layered" model and carried out the full-band-structure calculation of the frequency-dependent linear and nonlinear susceptibilities for both a ZnO bulk crystal and for our ZnO layered model. By comparing the results of the bulk and layered model, we find that the surface plays a significant role in determining the second harmonic response of ZnO but has no significant effects on the dielectric function. The calculated results for the dielectric function are compared to the experiment results. Also in this thesis, the electronic surface states are calculated using our layered model. The technique of numerical integration used in the susceptibility calculation is presented and discussed.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- January 1994
- Bibcode:
- 1994PhDT........20Y
- Keywords:
-
- ZINC OXIDE;
- Physics: Condensed Matter; Physics: Optics