由于超导准粒子导致的电磁散射的连贯抑制
Ioan M Pop1, Kurtis Geerlings1, Gianluigi Catelani2
11] Department of Applied Physics, Yale University, 15 Prospect Street, New Haven, Connecticut 06511, USA [2].
Nature
|April 18, 2014
概括
研究人员观察到了约瑟夫森连接中准粒子散射的量子连贯抑制. 这一发现增强了超导量子比特中的能量放松时间,最大限度地减少了量子信息处理的脱凝.
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
- 超导电性 超导电性 超导电性
背景情况:
- 约瑟夫森连接对于量子技术至关重要,因为超导体中的低损失信号传播.
- 由准粒子激发引起的约瑟夫森连接处内的射频信号的消散仍然是一个挑战.
- 在相差为π的情况下消失的准粒子散射的理论预测尚未在实验中得到证实.
研究的目的:
- 实验观察约瑟夫森连接中的准粒子散射的量子连贯抑制.
- 为了研究约瑟夫森连接处消散背后的机制.
- 为了证明这种抑制对改进量子系统的潜力.
主要方法:
- 在超导人工原子中测量能量放松时间的实验测量.
- 横扫约瑟夫森交叉点的平均相位偏差,通过π.
- 观察准粒子激发对信号散射的影响.
主要成果:
- 实验证实了量子连贯抑制准粒子散射的实验证实.
- 作为相位偏差观察到的能量放松时间增加了十倍以上,达到π.
- 证明了尽管存在准粒子激发,但仍然可以抑制散射.
结论:
- 这项研究通过实验验证了约瑟夫森关于在 π 阶段偏差下消失的准粒子散射的预测.
- 量子连贯抑制消散提供了一种方法,以最大限度地减少超导量子系统中的脱连贯性.
- 这一发现对通过超导量子比特推进量子信息处理有直接影响.
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