Substrate Index Dependence of Energy Levels in In_(0.4) Ga_(0.6) As/GaAs Quantum Dots Applicable to QD-Lasers (a six-band k.p approximation)

Esfandiar Rajaei; Mahdi Ahmadi Borji

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arXiv · 1511.00997

Substrate Index Dependence of Energy Levels in In_(0.4) Ga_(0.6) As/GaAs Quantum Dots Applicable to QD-Lasers (a six-band k.p approximation)

Esfandiar Rajaei·Mahdi Ahmadi Borji

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Abstract

Quantum dot lasers have been the focus of researchers due to their interesting optical properties owing to quantum confinement of carriers. In epitaxial quantum dots formed on a substrate, band-edge diagrams sound to more complex than simple bulk materials because of the important role of strain. Strain tensor is strongly dependent to lattice mismatch. Various substrate indexes have been used in the laser devices, and a number of research groups elaborate to find the best substrate index. In this research band edge, energy levels and strain effects of cubic In_0.4 Ga_0.6 As-GaAs quantum dots are studied by 6-band k.p model and their dependence to substrate index is investigated. It is shown that change of substrate index affects the band gap and transition energy of electrons and holes. Moreover, we show that components of strain tensor are strongly sensitive to surface index, and symmetry breaks along space. Our results appear to be in very good consonance with represented formula and similar researches. Keywords: substrate index, quantum dot laser, band edge, strain tensor.

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Esfandiar Rajaei, Mahdi Ahmadi Borji. 2015-11-01. Substrate Index Dependence of Energy Levels in In_(0.4) Ga_(0.6) As/GaAs Quantum Dots Applicable to QD-Lasers (a six-band k.p approximation). https://arxiv.org/abs/1511.00997

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