A silicon-based surface code quantum computer

作者：O'Gorman Joe; Nickerson Naomi H; Ross Philipp; Morton John J L^*; Benjamin Simon C^*

来源：npj Quantum Information, 2016, 2(1): 15019.

DOI：10.1038/npjqi.2015.19

Individual impurity atoms in silicon can make superb individual qubits, but it remains an immense challenge to build a multi-qubit processor: there is a basic conflict between nanometre separation desired for qubit-qubit interactions and the much larger scales that would enable control and addressing in a manufacturable and fault-tolerant architecture. Here we resolve this conflict by establishing the feasibility of surface code quantum computing using solid-state spins, or `data qubits', that are widely separated from one another. We use a second set of `probe' spins that are mechanically separate from the data qubits and move in and out of their proximity. The spin dipole-dipole interactions give rise to phase shifts; measuring a probe's total phase reveals the collective parity of the data qubits along the probe's path. Using a protocol that balances the systematic errors due to imperfect device fabrication, our detailed simulations show that substantial misalignments can be handled within fault-tolerant operations. We conclude that this simple `orbital probe' architecture overcomes many of the difficulties facing solid-state quantum computing, while minimising the complexity and offering qubit densities that are several orders of magnitude greater than other systems.

• 出版日期2016-2-2