Electronic, optical, and structural properties of quantum wire superlattices on vicinal (111) GaAs substrates

Abstract

We have studied corrugated quantum wells as a semiconductor quantum wire structure. The quantum well corrugation results from a step bunching effect during epitaxial growth on vicinal ͑111͒ GaAs substrates and might be used to form a quantum wire superlattice. The strain and piezoelectric effects were studied both by an atomistic valence force field method and by an elastic continuum model. Within the elastic continuum model we also studied the electromechanical coupling. The electronic band structure was calculated with the eightband k·p model. The nonphysical oscillating solutions were eliminated by appropriate fine tuning of the material parameters. We have also studied the density of states and the polarization dependence of interband light absorption in the electric dipole approximation.

Choosing a basis that eliminates spurious solutions ink∙ptheory

“…If not, a valid alternative to setting Ā = 0 is to choose a value of P 2 within this interval, 7 preferably near the upper bound P 0 2 in order to minimize ⌬P. For typical semiconductors, both ͉E g L ͉ Ӷ P 2 and ͉⑀ 1 A ͉ Ӷ P 2 , so the changes in the Hamiltonian are small regardless of whether P 0 2 is equal to P c 2 or P v0 2 .…”

“…4 Today this model is still used frequently for the study of medium-and narrow-gap nanostructures. [5][6][7][8][9][10][11][12][13] Kane's theory has a notorious pitfall: spurious solutions with large crystal momentum k, which arise from small Hamiltonian matrix elements of order k 2 .…”

Cooling of radiative quantum-dot excitons by terahertz radiation: A spin-resolved Monte Carlo carrier dynamics model

“…For more details on the electronic structure calculations see Ref. 23. The material parameters used in the eightband k · p calculations are listed in Table II.…”

“…The value of the conduction-valence band coupling parameter E p , given in Table II, has been reduced in order to avoid spurious states (see Ref. 23, and references therein). However, the effect of the reduction of E p on the effective masses was negligible (this was verified by testing the model for the pertinent bulk semiconductors).…”

“…This was motivated by the large geometry, spanning over ∼ 10 8 atoms and the possibility to include piezoelectric coupling in the model. In the coupled electroelastic field formulas, the vectors of the stress T and the electric flux D are related to the strain S and the electric field E as [23] …”