Donor and superconducting quantum computer architectures: challenges and prospects - Austin Fowler

After a review of the physical resources required to efficiently implement quantum error correction and fault-tolerant computation, I describe the latest ideas of how one might build a quantum computer using firstly phosphorus atoms in silicon and secondly superconducting components. In both cases, fundamentally unscalable ideas such as field gradients, fixed frequency selectivity, and serial gates are avoided. Global oscillating fields and high qubit densities leading to severe crosstalk problems are also avoided. Indeed, the architectures presented can be scaled to arbitrarily large numbers of qubits without making the construction or operation of a fixed unit length of the computer any more difficult.