Adiabatic charge control in a single donor atom transistor

We charge an individual donor quantum dot with an electron originally stored in another quantum dot in its proximity. The single arsenic donor quantum dot and the electrostatic quantum dot in parallel are contained in a silicon nanometric field effect transistor. Their different coupling capacitances with the control and back gates determine a honeycomb pattern at high control gate voltage. It is therefore possible to control the exchange coupling of an electron of the quantum dot with the electrons bound to the donor quantum dot toward the realization of a physical qubit for quantum information processing applications.