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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2008. V. 11, N 4. P. 364-369.
Strain effects on the valence band structure,
optical transitions, and light gain spectra
in zinc-blende GaN quantum wells
V. Lashkaryov Institute for Semiconductor Physics, Department of Theoretical Physics,
41, prospect Nauky, 03028 Kyiv, Ukraine, e-mail: lyuba.lokot@gmail.com
Abstract. A study for the effects of size quantization and strain effects on the valence
band spectra, the interband matrix elements, and the light gain spectrum in zinc-blende
GaN quantum wells is presented. In the framework of the effective mass theory, the
Schrödinger equation is solved for the valence bands with a 3×3 block Hamiltonian. The
results are illustrated for the GaN/Al 0.19 Ga 0.81 N quantum well. It is shown, that the biaxial
strain causes quite significant changes to the gain spectra in spatially confined structures.
It is shown, that laser effect is suppressed with arising of the circular loop of valence
band maxima in the heterostructure under the tensile strain, while under the compressive
strain, the stimulated emission is pronounced. Our results show the internal strain effects
are important in optical properties of GaN and associated quantum well structures.
Keywords: strain effect, valence band structure, optical transition, light gain spectra,
zinc-blende GaN, quantum well.
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