约瑟夫森结点的微观结构和电气性能通过热变化而改变
Nikita D Korshakov1,2, Dmitry O Moskalev1,2, Anastasia A Soloveva1,2
1FMN Laboratory, Bauman Moscow State Technical University, Moscow, Russia, 105005.
Scientific reports
|October 31, 2024
概括
制造后的热回火提高了超导量子处理器的约瑟夫森连接的可重现性. 这种方法提高了连接电阻,并使精确的量子比特频率调整成为可能,这对于可扩展的量子计算至关重要.
科学领域:
- 量子计算是一种量子计算.
- 材料科学 材料科学 材料科学
- 超导电性 超导电性 超导电性
背景情况:
- Al/AlOx/Al Josephson连接的可重复性对于扩展超导量子处理器至关重要.
- 约瑟夫森结的微观结构和电性质的制造变化导致了跨子量子比特的频率不确定性.
研究的目的:
- 介绍制造后的热回火工艺,以提高约瑟夫森连接的可重复性.
- 为了使固定频率的超声量子比特能够进行可扩展的频率修剪.
主要方法:
- 在Al/AlOx/Al Josephson连接处使用热后曝光回火方法.
- 研究了连接电阻的温度和时间依赖性.
- 分析了电极尺寸和侧墙贡献对电阻的影响.
- 基于氧气度梯度的道屏障修改开发了一个理论模型.
主要成果:
- 实现了连接阻力的175%的增加.
- 在10%的步骤 (Rn) 中,抵抗下降了60%.
- 观察到强烈的温度依赖性和阻力的弱持久时间依赖性.
- 确定了电极尺寸和侧壁对后电阻的显著影响.
结论:
- 热回火工艺为稳定和可重复的道屏障提供了解决方案.
- 这种方法为跨子量子比特提供了可扩展的频率修剪.
- 这些发现有助于超导量子计算硬件的发展.
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