Electronic properties of coupled quantum dots

In the work two coupled quantum dots (CQDs) are analyzed. They are formed electrostatically in GaAs/AlGaAs heterostructure. Calculations are performed with the use of the three-dimensional (3D) numerical model of the device. The results are obtained for the structure working under the special biasing conditions. At some characteristic values of biasing voltages the transfer of the charge from one quantum well to the other is observed. Charge density distribution in the CQDs is obtained on the basis of the electronʹs wave functions. They are calculated as the self-consistent solutions of Poisson and Schrödinger equations in 3D space. Charge density corresponds to the effective potential distribution which contains Hartree term of the potential and the two other terms which describe the effects of exchange and correlation in electron–electron interactions. These effects are modeled by the use of the local density approximation (LDA).