长距离运输在合量子井中的激发性暗态中
1Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara Street, Pennsylvania 15260, USA. snoke@pitt.edu
Nature
|August 16, 2002
概括
观察到,InGaAs量子井中的刺激子可以传输数百微米,远远超出它们的典型扩散极限. 这种远程传输通过黑暗状态发生,然后集体恢复到发光状态.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子光学就是一个量子光学.
- 半导体异构结构中的半导体.
背景情况:
- 结合的量子井被研究了激子的斯-爱因斯坦凝聚.
- 量子井中的兴奋子传输通常仅限于几微米,这是由于寿命短和散射.
- 激子的长距离连贯传输是研究的一个关键领域.
研究的目的:
- 为了研究在InGaAs量子井中的激子运输.
- 观测和描述超出典型的扩散极限的远程激子传输.
- 探索潜在的机制,如斯凝结,是这种现象的基础.
主要方法:
- 测量印化 (InGaAs) 量子井的光发光度.
- 激光激发产生激发子.激发子.激发子.
- 对光发光的空间映射,以观察激子分布.
主要成果:
- 从激光激发点数百微米处出现的激发子发光的观测.
- 发光在激发点周围形成一个环,中间的辐射最小.
- 刺激子似乎在非发光 (黑暗) 状态下旅行,然后在临界距离处集体变为发光.
结论:
- 在量子井中观察到一种新的长距离传输机制,用于量子井中的激子.
- 观察到的现象表明,刺激子可能在黑暗状态下在相当长的距离上旅行.
- 这种效应与斯-爱因斯坦凝聚和宏观连贯性之间的关系需要进一步研究.
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