在具有弱磁场的超导量子体中1/f流噪声的演变
David A Rower1,2, Lamia Ateshian2,3, Lauren H Li1
1Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Physical review letters
|June 16, 2023
概括
这项研究研究了超导电路中的1 / f磁流噪声,揭示了磁场如何影响量子位变相. 结果表明,增加的旋转集群大小有助于噪声动态,有助于理论发展.
科学领域:
- 量子计算是一种量子计算.
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 超导电路中的1 / f磁流噪声的微观起源是一个长期存在的问题.
- 了解这种噪音对于减轻量子信息处理中的量子位脱来说至关重要.
- 表面旋转是主要的候选者,但它们的具体性质和相互作用尚未完全理解.
研究的目的:
- 为了研究超导电路中的1 / f磁流噪声的微观机制.
- 探索弱磁场对量子位变相和噪声光谱的影响.
- 提供实验数据,可以为流量噪声的理论模型提供信息.
主要方法:
- 将弱的平面内磁场应用于容量偏移的流量量子位.
- 使用自旋回声和拉姆齐技术测量流量噪声限制量子位变相.
- 执行各种频率和磁场强度的直接噪声光谱.
主要成果:
- 观察到旋回回声的增强和拉姆齐脱相时间的抑制,随着磁场的增加 (高达100G).
- 检测到从1/f到洛伦兹噪声频谱的过渡在10 Hz以下.
- 随着磁场强度的增加,注意到1MHz以上的噪声减少.
结论:
- 观察到的趋势与表面旋转集群大小在应用磁场下的增加是一致的.
- 这些发现为1/f流噪声的动态提供了新的见解.
- 结果为开发超导器件流量噪声的综合微观理论提供了关键数据.
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