The effect of Woods–Saxon potential on envelope function, intersubband dispersion curves and group velocity of InAs/GaAs quantum dots with wetting layer

• The Schrödinger equation for InAs/GaAs quantum dots/wetting layer system is solved numerically using a finite element method (FEM).
• Woods–Saxon potential is applied to quantum dots as well as a constant finite barrier between InAs quantum dot/wetting layer and GaAs matrix is considered for comparison.
• The envelop wavefunction for both constant and WS potentials is investigated.
• The effect of Woods–Saxon potential on linear susceptibility and group velocity is explored for different radii of dome-shaped InAs/GaAs quantum dot.

In this study, one band Schrödinger equation for InAs/GaAs quantum dots coupled to their wetting layer was solved numerically by using a finite element method (FEM). We have carried out the conduction of the Woods–Saxon (WS) potential in the quantum dots (QDs) as well as a constant finite barrier between InAs quantum dot/wetting layer and GaAs matrix is considered for comparison. It is found by WS potential that the envelope functions never become completely localized inside the dot; therefore this delocalization leads to strong alternations in absorption and dispersion profiles which is not negligible. Also, it is found that group velocity is affected by the WS potential and reveals remarkable blue-shift in comparison to the constant finite potential.

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