A quantum processing system is disclosed. In one embodiment, a quantum processing system comprises: a plurality of donor atoms positioned in a silicon crystal substrate, each donor atom positioned at a donor site; and a plurality of conductive control electrodes arranged about the donor atoms to operate the donor atoms as qubits. Where, at least two pairs of nearest neighbour donor atoms of the plurality of donor atoms are arranged along the [110] direction of the silicon crystal substrate and are configured to operate as qubits.