ELECTRON TRANSPORT IN CENTERED DEFECT QUANTUM DOTS MOLECULE

摘要

The electronic conductance of centered defect quantum dots (QDs) molecule is modeled using the two-dimensional transfer matrix method. The proposed model is based on the scattering formalism. We show that inserting defects in QDs, causes blue-shift in conductance as well as decreasing the distance between mini-bands (conductance gap). It is shown that increasing the defect size leads to a large blue-shift and also conductance gap decreases more. When defect is inserted in one QD, due to different energy contents of quantum dots (with and without defect), the coupling between these elements introduces a new separated transmission peak in the conductance. It should be mentioned that in the molecule with original QDs or two centered defect QDs, there isn't such a behavior. Also the concept of step quantum dots molecule is proposed for first time in this paper and its conductance properties is investigated. The proposed ideas in this paper, opens a new insight to design super molecule based on centered defect quantum dots for given electronic conductance.