  Prospects for the quantum control of electrons in the silicon quantum
computer architecture are considered theoretically. In particular, we
investigate the feasibility of shuttling donor-bound electrons between the
impurity in the bulk and the Si-SiO2 interface by tuning an external electric
field. We calculate the shuttling time to range from sub-picoseconds to
nanoseconds depending on the distance (~ 10-50 nm) of the donor from the
interface. Our results establish that quantum control in such nanostructure
architectures could, in principle, be achieved.
