悬挂债券是可能导致和-量子点量子比特中的电荷噪声的贡献者
Joel B Varley1, Keith G Ray1, Vincenzo Lordi1
1Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States.
ACS applied materials & interfaces
|August 31, 2023
概括
悬挂债券是量子点量子比特中电荷噪声的主要原因. 缓解这些缺陷对于提高量子计算性能和设备可靠性至关重要.
科学领域:
- 量子计算是一种量子计算.
- 材料科学是一种材料科学.
- 半导体物理 半导体物理
背景情况:
- 基于的自旋量子比特提供了很长的连贯时间,但受到电荷噪声的限制.
- 了解电荷噪声的起源对于推进量子点量子比特的真实性至关重要.
研究的目的:
- 研究Si/SiGe量子点中的电荷噪声的原子源.
- 专注于在和悬浮键 (DB) 上捕获电荷.
主要方法:
- 利用混合功能计算来研究缺陷水平.
- 分析了使用配置坐标图的捕获和激发能量.
- 在SiGe异构结构中考虑过压力和氧化等环境因素.
主要成果:
- 在SiGe合金和氧化物中确定了悬挂键作为重要的电荷捕获中心.
- 发现组成的不均性可能会恶化电荷捕获.
- 评估了应变和氧化对缺陷能量学的影响.
结论:
- DB是Si基量子点量子比特中电荷噪声的主要来源.
- 合金的一致性和悬挂键被动化对于量子比特性能至关重要.
- 这些发现与Si,Ge和SiGe金属氧化物半导体设备有关.
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