Electronic properties of single and coupled anisotropic quantum dots in a magnetic field, spin interactions and switching

We determined the eigenstates of a single electron in a parabolic anisotropic 2D quantum dot in a magnetic field. Using obtained expressions for these eigenstates, we study the spin coupling J between two electrons located in two laterally coupled anisotropic quantum dots (QD). The exhange coupling J is calculated using the Heitler-London and Hund-Mulliken approaches. We found that the exhange J changes sign at certain values of parameters of the system, in particular at certain anisotropy of the QD. Therefore, we present a new method to switch on and off the spin coupling between QD: switching by means of changing shape of the QD. Switching the spin coupling is essential for quantum computation using electronic spins as qubits. We note that our calculations can be applied to the system of vertically coupled QD as well.