一致的零状态和pi状态在激子-极子凝聚剂阵列中
C W Lai1, N Y Kim, S Utsunomiya
1E. L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. cwlai@stanford.edu
Nature
|November 23, 2007
概括
研究人员观察到半导体微腔内的激子-极子凝聚体中自发的相位和反相位超流体状态,反映了在斯-爱因斯坦凝聚体中看到的现象.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子光学是一种量子光学.
- 材料科学 材料科学 材料科学
背景情况:
- 在多粒子系统中的量子统计导致了诸如超流动性和超导性之类的集体性质.
- 斯-爱因斯坦凝聚物表现出离对角长距离的顺序,并具有连贯波函数的特征.
- 已知超流体和超导约瑟夫森连接处的相锁定凝聚物和pi状态.
研究的目的:
- 为了研究自发形成的在相和反相超流体状态.
- 为了在固态系统中探索这些现象,特别是激子-极子凝聚物.
- 为了将这些状态与底层带结构和极子子阵列的动态联系起来.
主要方法:
- 一个半导体微腔的制造,其中包含一系列激子-极子凝聚物.
- 引入弱周期电位障碍来合冷凝物.
- 观察和特征自发的在相 (零状态) 和反相 (pi状态) 形成.
主要成果:
- 证明了相内和反相超流体状态的自发积累.
- 在固态系统中的一组合激子-极子凝聚物中观察到这些状态.
- 将观察到的状态与一维极子阵列的带结构相关联.
结论:
- 半导体微腔中的刺激极子凝结物可以呈现自发的相内和反相超流体状态.
- 这些发现为研究量子连贯性和相位现象提供了一个固态平台,类似于斯-爱因斯坦凝结体.
- 观察到的状态与极子系统独特的带结构和动态特性有关.
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