三光子的挤压和过挤压
L K Shalm1, R B A Adamson, A M Steinberg
1Centre for Quantum Information and Quantum Control, Institute for Optical Sciences, Department of Physics, University of Toronto, 60 St George Street, Toronto, Ontario, Canada M5S 1A7. lshalm@physics.utoronto.ca
Nature
|January 6, 2009
概括
研究人员使用一种新的光学系统实现了接近海森堡限制的旋转挤压. 通过三光子的突破,可以实现用于精确测量和信息处理的新量子技术.
科学领域:
- 量子光学是一种量子光学.
- 量子信息科学 量子信息科学
- 计量学 计量学 计量学
背景情况:
- 量子力学为测量准确性定义了一个标准的量子极限,不确定性通常在互补性质之间共享.
- 旋转挤压,一种在这个极限以下的一个属性中减少不确定性的技术,对于量子光物质接口至关重要,但远离理论上的海森堡极限.
- 现有的光学自旋压缩系统已经取得了进展,但仍然低于可实现的最大压缩的数量级.
研究的目的:
- 为了证明光学旋转挤压接近基本的海森伯格不确定性极限.
- 探索使用少数光子系统的自旋挤压状态的产生和性质.
- 研究球形拓在限制挤压和"过度挤压"现象中的作用.
主要方法:
- 通过在光纤中叠加三个无法区分的光子来产生自旋挤压状态.
- 操纵光子极化 (旋转) 以形成一个"三光子",一个压缩的复合粒子.
- 使用球形表面上的准概率分布对三光子状态的表征.
主要成果:
- 证明了光学旋转挤压,基本上达到基本的海森堡不确定性极限.
- 观察到"过度挤压",由于偏振的球形拓,准概率分布围绕球体.
- 在少数光子模式下成功创建和特征化了自旋挤压状态.
结论:
- 开发的光学系统允许旋转挤压接近理论最大值,克服了以前的限制.
- 这些发现突出了球形拓对量子挤压的影响,并引入了"过度挤压"的概念.
- 这项工作为新的量子资源铺平了道路,用于在光子水平上进行增强的测量,光刻和信息处理.
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