编码一个超越亏平衡的魔法状态
Riddhi S Gupta1,2, Neereja Sundaresan1, Thomas Alexander1
1IBM Quantum, T. J. Watson Research Center, Yorktown Heights, NY, USA.
Nature
|January 10, 2024
概括
研究人员开发了一种量子错误校正方案, 这种方法使用杂的量子比特提高了逻辑门的质量,为更有效的量子算法铺平了道路.
科学领域:
- 量子计算
- 量子错误纠正
背景情况:
- 量子计算机需要纠错代码来执行逻辑门并保护信息免受噪音的影响.
- 魔力状态是完成量子计算中的通用逻辑门集的重要资源.
- 对于最小化量子算法中的噪音, 高准确度的魔法状态准备非常重要.
研究的目的:
- 在超导量子比特阵列上使用量子错误校正来准备和实施一种新的方案.
- 证明错误纠正可以提高杂量子比特产生的逻辑门的质量.
- 展示自适应电路在增加魔力状态的效用,用于量子错误的纠正.
主要方法:
- 在超导量子比特阵列上实现量子错误校正方案.
- 使用建议的错误纠正技术准备魔法状态.
- 适应性电路的应用与中间电路测量,以优化魔法状态的产生.
主要成果:
- 与使用单个量子比特制备的比特币相比,实施的方案成功产生了更高可靠性的魔法状态.
- 使用错误校正证明了使用杂量子比特提高逻辑门质量的原则.
- 适应性电路被证明可以增加魔力状态的产量,这是错误校正子程序的关键功能.
结论:
- 开发的方案提供了一种用于产生对容错量子计算至关重要的高保真性魔力状态的方法.
- 这项工作验证了量子错误校正可以提高杂量子比特的性能的基本原理.
- 这种原型能够减少物理量子比特的开销, 这对于未来的大规模量子计算架构具有重要意义.
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