Defects in Square 2D Arrays of Strained Quantum Dots

摘要

A theoretical model is suggested which describes quantum dot ensembles of the new type, namely the quantum dot arrays with defects. These defects represent local violations of the geometry of 2D arrays formed by quantum dots on crystalline substrates. The elastic moduli of strained arrays of quantum dots are estimated, in which case strains describe deviations of spatial positions of quantum dots from nodes of ideal square arrays. The formulas for characteristic energies of dislocations, disclinations and point defects in 2D arrays of quantum dots are derived. It is shown that point defects are characterized by comparatively low values of the formation energy and, therefore, are capable of being intensively formed in quantum dot arrays fabricated at highly non-equilibrium conditions.