在超导量子位中观察一个连贯的两级系统的离散电荷状态
Bao-Jie Liu1, Ying-Ying Wang1, Tal Sheffer1
1University of Massachusetts-Amherst, Department of Physics, Amherst, Massachusetts, USA.
Physical review letters
|November 1, 2024
概括
研究人员观察到两级系统 (TLS) 与超导量子比特相结合的不同电荷状态. 这些微波频率TLS作为低频电荷噪声的来源,影响量子比特性能.
科学领域:
- 量子计算是一种量子计算.
- 超导电路中的超导电路.
- 量子信息科学是一种量子信息科学.
背景情况:
- 超导量子比特对充电噪声敏感,这可能会限制它们的连贯性.
- 双层系统 (TLS) 是超导电路中常见的缺陷,可以作为噪声源.
研究的目的:
- 为了研究与超导超声量子比特紧密合的双层系统 (TLS) 的电荷状态.
- 为了量化TLS和量子比特之间的合参数.
- 为了确定TLS过渡是否与准粒子道化动态相关.
主要方法:
- 采用了一种对偏移电荷敏感的超导电晶体量子比特.
- 在强分散和强共振模式下进行测量.
- 同时跟踪TLS过渡和准粒子道动态.
主要成果:
- 观察到一个连贯的TLS的离散电荷状态,其偏移电荷为0.072e.
- 测量了2.9 GHz的TLS过渡频率和超过3 ms的放松时间.
- 量化了TLS-量子位相互作用的横向和纵向合.
- 没有发现TLS过渡和准粒子道之间的内在相关性.
结论:
- 证明微波频率TLS可以作为低频电荷噪声的来源.
- 为特征TLS-量子位相互作用提供了一种方法.
- 强调了解和减轻超导量子比特中的TLS噪声的重要性.
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