一个经过纠错的量子位的容错控制
Laird Egan1,2,3, Dripto M Debroy4,5, Crystal Noel6,7
1Joint Quantum Institute, Center for Quantum Information and Computer Science, University of Maryland, College Park, MD, USA. laird.egan@gmail.com.
Nature
|October 5, 2021
概括
在真实量子系统中演示了容错电路, 显著减少了错误. 这一突破使得量子计算更加精确,并为强大的量子计算铺平了道路.
科学领域:
- 量子信息科学
- 实验量子计算
- 量子错误纠正
背景情况:
- 量子错误校正将信息编码到更大的系统中, 以保护其免受噪声的影响.
- 控制编码的量子比特增加了复杂性,
- 之前的故障耐受性电路演示缺乏现实世界的量子系统噪声.
研究的目的:
- 在经过纠错的物理系统中实验性地展示耐故障电路.
- 对原生噪声特征的故障耐受性协议的有效性进行评估.
- 为了确定精确的逻辑量子比特操作的可行性.
主要方法:
- 使用13个被困的离子量子位来实现容错电路.
- 开发并测试了培根-肖尔逻辑量子位的准备,测量,旋转和稳定器测量协议.
- 在现实的噪音条件下,将耐故障协议与非耐故障协议进行比较.
主要成果:
- 与非容错方法相比,实现了逻辑原始的错误率显著降低.
- 在错误纠正后,平均状态准备和测量误差为0.6%,Clifford gate误差为0.3%.
- 准备的魔力状态超过了蒸门,展示了关键的单量子位容错控制元件.
结论:
- 在当前的量子系统中, 容错电路能够实现高度精确的逻辑操作.
- 实验演示验证了耐故障设计原则的实际应用.
- 两位量子比特门的进一步改进和中间测量可以导致稳定的逻辑量子比特.
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