半导体纳米结构中自旋连贯性的电气控制
1Center for Spintronics and Quantum Computing, University of California, Santa Barbara, California 93106, USA.
Nature
|December 12, 2001
概括
研究人员在一个新的AlxGa1-xAs量子井中演示了电子自旋连贯性的电控制. 这一突破使得自旋分裂的操纵能够用于量子信息处理,即使在室温下也是如此.
科学领域:
- 量子信息科学 量子信息科学
- 凝聚物质物理学 凝聚物质物理学
- 半导体螺旋电子学 半导体螺旋电子学
背景情况:
- 量子信息处理依赖于对电子旋转的连贯操纵.
- 目前用于控制旋转分裂的方法通常需要在小尺度上精确控制磁场.
- 另一种方法涉及半导体异构结构中的电门,具有不同的g因子.
研究的目的:
- 为了证明门电压介导的控制连贯的旋转前行.
- 探索使用分级的AlxGa1-xAs量子井用于旋转操纵.
- 为了控制旋转分裂和前行频率.
主要方法:
- 一个专门设计的AlxGa1-xAs量子井的制造,其度 (x) 为等级的 (Al).
- 电场的应用,以在量子井内取代电子波函数.
- 使用时间解析的光学技术来测量和控制旋转前行.
主要成果:
- 在13GHz频率范围内,证明了门电压介导的连贯旋转前行控制.
- 完全抑制了旋转前行和反转g因子符号.
- 展示了高达室温的操作能力.
结论:
- 一个分级的AlxGa1-xAs量子井允许电气控制电子自旋分裂和连贯性.
- 这种方法为可扩展的量子信息处理提供了一个有希望的途径.
- 经过证明的室温操作是自旋电子设备的重大进步.
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