Kavli Institute of Nanoscience, Delft University of Technology, PO Box 5046, 2600 GA Delft, The Netherlands.
1] Kavli Institute of Nanoscience, Delft University of Technology, PO Box 5046, 2600 GA Delft, The Netherlands [2].
Nat Nanotechnol. 2014 Mar;9(3):171-6. doi: 10.1038/nnano.2014.2. Epub 2014 Feb 2.
Quantum registers of nuclear spins coupled to electron spins of individual solid-state defects are a promising platform for quantum information processing. Pioneering experiments selected defects with favourably located nuclear spins with particularly strong hyperfine couplings. To progress towards large-scale applications, larger and deterministically available nuclear registers are highly desirable. Here, we realize universal control over multi-qubit spin registers by harnessing abundant weakly coupled nuclear spins. We use the electron spin of a nitrogen-vacancy centre in diamond to selectively initialize, control and read out carbon-13 spins in the surrounding spin bath and construct high-fidelity single- and two-qubit gates. We exploit these new capabilities to implement a three-qubit quantum-error-correction protocol and demonstrate the robustness of the encoded state against applied errors. These results transform weakly coupled nuclear spins from a source of decoherence into a reliable resource, paving the way towards extended quantum networks and surface-code quantum computing based on multi-qubit nodes.
与单个固态缺陷中的电子自旋耦合的核自旋量子寄存器是量子信息处理的有前途的平台。开创性的实验选择了具有特别强的超精细耦合的有利位置的核自旋的缺陷。为了朝着大规模应用发展，更大和可确定的核寄存器是非常需要的。在这里，我们通过利用丰富的弱耦合核自旋来实现多量子比特自旋寄存器的通用控制。我们使用金刚石中的氮空位中心的电子自旋来选择性地初始化、控制和读出周围自旋浴中的碳-13 自旋，并构建高保真度的单量子比特和双量子比特门。我们利用这些新功能来实现一个三量子比特量子纠错协议，并证明编码状态对施加的错误的鲁棒性。这些结果将弱耦合核自旋从退相干的来源转变为可靠的资源，为基于多量子比特节点的扩展量子网络和表面码量子计算铺平了道路。
