Materials Research Society Symposium Proceedings 468, 251 (1997).
Below is the abstract submitted to the meeting, not the abstract of the published paper:
In order to give the important guideline on the GaN-based device design, the electronic and optical properties of the III-V nitrides and their quantum well (QW) structures have been theoretically investigated. The electronic structures and optical gains of bulk GaN and GaN/AlGaN QW are discussed from the point of view of the laser‘s characteristics. The analyses were performed for the wurtzite and zincblende structures on the basis of the k(I%(Jp and tight-binding methods, comparing with the other III-V compounds. The fundamental physical parameters have been derived from the first-principles calculations. It was found that the lower crystal symmetry, that is the wurtzite, is preferable for the lower threshold current density in the bulk GaN. Although the introduction of QW structures leads to symmetry lowering only in the zincblende QW, we can not find a significant benefit of the zincblende QW. As for the strain effect on the reduction of the threshold current density, the pseudomorphic biaxial strains are more effective in the zincblende as in the wurtzite. However, the threshold current density of the biaxial strained QW is still higher in the zincblende than in the wurtzite. It was also found that the uniaxial strain in the c-plane of the wurtzite is more useful for reducing it. The relation between the uniaxial strain‘s direction and the optical polarization is also clarified. We will discuss how to reduce the threshold current density and the effect of lattice defects on the optical transition, as well.
This paper is part of Gallium Nitride and Related Materials II
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