A trapped-ion-based quantum byte with 10−5 next-neighbour cross-talk
A trapped-ion-based quantum byte with 10−5 next-neighbour cross-talk
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DOI：
10.1038/ncomms5679
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发表时间：
2014-03
影响因子：
16.6
通讯作者：
C. Piltz;T. Sriarunothai;A. F.Var'on;Ch. Wunderlich
中科院分区：
文献类型：
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作者：
C. Piltz;T. Sriarunothai;A. F.Var'on;Ch. Wunderlich
在量子寄存器内对特定量子位的寻址是可扩展量子计算的关键先决条件。一般来说，用单个量子比特或量子比特的子集执行量子门会影响所有其他量子比特的量子态。全量子寄存器的这种降低的保真度可能会阻止量子纠错协议的应用，从而妨碍可扩展性。在这里，我们演示了在一个量子字节（8个量子位）内对单个量子位的寻址，并测量了与单量子位门应用相关的所有未寻址量子位（串扰）中引起的误差。量子字节是使用微波驱动的171 Yb+离子的超精细量子比特限制在一个保罗陷阱增强的磁梯度场。测得的串扰约为10 - 5，因此低于通常认为足以有效实现容错量子计算的阈值。因此，我们的研究结果证明了如何克服这个阈值的串扰。
The addressing of a particular qubit within a quantum register is a key pre-requisite for scalable quantum computing. In general, executing a quantum gate with a single qubit, or a subset of qubits, affects the quantum states of all other qubits. This reduced fidelity of the whole-quantum register could prevent the application of quantum error correction protocols and thus preclude scalability. Here we demonstrate addressing of individual qubits within a quantum byte (eight qubits) and measure the error induced in all non-addressed qubits (cross-talk) associated with the application of single-qubit gates. The quantum byte is implemented using microwave-driven hyperfine qubits of171Yb+ions confined in a Paul trap augmented with a magnetic gradient field. The measured cross-talk is on the order of 10−5and therefore below the threshold commonly agreed sufficient to efficiently realize fault-tolerant quantum computing. Hence, our results demonstrate how this threshold can be overcome with respect to cross-talk.