Architectures of donor-electron based qubits in silicon near an oxide
interface are considered theoretically. We find that the precondition for
reliable logic and read-out operations, namely the individual identification of
each donor-bound electron near the interface, may be accomplished by
fine-tuning electric and magnetic fields, both applied perpendicularly to the
interface. We argue that such magnetic fields may also be valuable in
controlling two-qubit entanglement via donor electron pairs near the interface.Comment: 4 pages, 4 figures. 1 ref and 1 footnote adde