Intersubband Transitions in the Quantum Dot Layers for Quantum Confined Photodetector

Bound to continuum intersubband transition optical properties in the strain reducing layer-assisted InAs quantum dot structure

“…The reason for choosing this well-established 'truncated cone' dot geometry for QD shape is attributed to the fact that, in the process of QD preparation, the GaAs capping layer alters the top part of QD shape with inserting strain, as the reported experimental TEM images in the most cases of QD growth [31]. In order to study numerically this model in conjunction with strain reducing layer (SRL), by the finite element method based programs, we have to define geometry of the system with finite size.…”

“…This model is well explored that the influences of strained interfaces of semiconductor materials, such as GaAs/In 0.1 Ga 0.9 As/ InAs, have been considered as deformation potentials of the band offset. In the author earlier publication and as reported in references [31,33] , the strain effects on the band structure has been calculated precisely in terms of the altering effective mass and the potential deformation causing changes in the electronic bands. In these calculations, the strain was assumed to be a constant value between the InAs QD and the surrounding InGaAs capping layer.…”

“…We have set base diameter 24 nm and SRL height 3 nm more than the QD varied height corresponding to References [31,3436]. The energy eigenvalues of the ground state (GS) and the WL state with and without considering SRL at several WL thicknesses are presented in Fig.…”

“…Based on the nonlinear optics formalism [31] the RI changes and the AC of the material can be calculated by…”

“…The QD structure was grown on In 0.1 Ga 0.9 As/GaAs substrate in (001) direction by using solid-state molecular beam epitaxy (MBE) [31]. The QD geometry is considered as a truncated cone with 24 nm in circular base diameter and 6nm top diameter with various heights.…”