在二维原子双层中高温激子凝聚的证据
Zefang Wang1, Daniel A Rhodes2, Kenji Watanabe3
1School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA.
Nature
|October 4, 2019
概括
研究人员在二维原子双层中观察到高温激子凝聚. 在二二 (MoSe2-WSe2) 中的这一发现为新的光电子和超导开辟了大门.
科学领域:
- 凝聚物质物理
- 材料科学
- 量子光学
背景情况:
- 在接近绝对零度的温度下形成波斯-爱因斯坦凝结物.
- 由于质量较小,预计激子在较高的温度下会凝结.
- 二维范德瓦尔斯半导体具有强大的激子结合,非常适合研究高温凝结.
研究的目的:
- 在MoSe2-WSe2原子双层中研究高温激子凝聚.
- 探索电力产生的层间激子的行为.
- 提供层间激电凝结及其潜在应用的证据.
主要方法:
- 使用了MoSe2-WSe2原子双层,激子密度高达10^12cm^2.
- 分析了间层道电流对激子密度的依赖性.
- 在凝结值附近测量了电光强度和光子统计.
主要成果:
- 观察到电光效应对激子密度的关键值依赖.
- 在相同的电子密度和孔密度下检测到超波伊森光子统计和显著的电光增强.
- 证明这种现象持续在100克尔文以上, 符合理论预测.
结论:
- 提供了二维原子双层中层间激子凝聚的证据.
- 突出了基于凝聚物的光电子技术的潜力.
- 开辟了探索激子介导的高温超导的途径.
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