机械振荡器在其热失干率上的基于测量的控制
D J Wilson1, V Sudhir1, N Piro1
1Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Nature
|August 11, 2015
概括
研究人员开发了一种用于量子反控制的新位置传感器. 这种传感器实现了前所未有的精度,使得纳米机械振荡器的冷却接近其基本状态,为大量物体的量子控制铺平了道路.
科学领域:
- 量子物理学
- 视觉机械
- 纳米技术
背景情况:
- 实时量子反协议使用连续测量记录稳定量子状态.
- 在微波光子和超导量子比特等微系统中存在成功的应用.
- 稳定巨大的物体,如机械振荡器, 由于环境的不一致性,
研究的目的:
- 开发一种能够识别纳米机械振荡器零点运动的位置传感器.
- 为了实现实时量子反控制,
- 克服巨大的量子系统中环境脱所带来的局限性.
主要方法:
- 一个高Q微空洞的光学机械合.
- 开发具有高精度和低不精度的位置传感器.
- 使用传感器作为反冷却的误差信号.
主要成果:
- 传感器在其热失干时间范围内解析4.3MHz纳米机械振荡器的零点运动.
- 在标准量子极限以下达到四个数量级的不精确度,
- 将振荡器从4.4K冷却到1.1±0.1mK,达到16%的基态概率.
结论:
- 开发的传感器为线性位置传感设定了新的基准.
- 证明量子反控制纳米机械振荡器的可行性.
- 这标志着机械振荡器作为量子控制的实际系统的出现.
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