The Electronic Structure of Truncated-Conical Shaped InAs/GaAs Quantum Dot With Wetting Layers

Semiconductor quantum dots have been of major interest in recent years. This has largely been simulated by progress in quantum dot growth technology, whereby self-organized quantum dots array can be achieved using Stranski-Krastanow growth mode. Quantum does material has achieved broad applications in optoelectronic devices and quantum information fields because of the unique 3-D electron confinement. Based on the 1-band effective-mass theory, a finite element technique is developed to calculate the electronic structure of conical shaped InAs/GaAs quantum dot, including the wetting layer. Using the axis-symmetry model, the 3-D effective-mass Schro¨dinger equation with step potential barrier can be reduced to a 2-D problem by separating variable, which greatly reduced the calculation cost. Based on the result, we found, compared without wetting layer, the wetting layer can influence the electron level. This may attribute to the increase of the confining potential width rather than the potential height. The presented finite element code can be further used to analysis the transverse or vertical coupled quantum dot molecule.