与Skyrmions打破对称性的动力学和拓学
J Pišljar1, A Nych1,2, U Ognysta2
1Condensed Matter Department, J. Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia.
Physical review letters
|May 10, 2024
概括
将奇拉性阴性液晶限制在薄层中,极大地减缓了斯基米昂的波动. 这种限制导致半斯基尔米翁碎片和取决于温度的拓电荷不平衡,揭示了局限拓材料中的新动态行为.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 软物质物理学 软物质物理学
- 液晶科学 液晶科学
背景情况:
- 状阴性液晶表现出复杂的拓结构,如天.
- 了解这些 skyrmions 的动态对于潜在的应用至关重要.
- 对软物质系统的限制效应可以导致独特的现象.
研究的目的:
- 为了研究纳米尺度封闭对在奇拉性阴性液晶中 skyrmions 的过渡前波动的影响.
- 描述 skyrmion 碎片的行为及其动态.
- 为了分析在 skyrmion 凝结过程中的拓电荷演变.
主要方法:
- 实验观测形阴性液晶,形成细层 (100 nm) 的螺旋晶体.
- 对过渡前顺序参数波动的分析.
- 波动的半斯基尔米翁碎片的特征.
- 取决于温度的拓电荷测量.
主要成果:
- 过渡前的斯基米翁波动在100nm薄层中减慢了四个数量级.
- 在特定的温度范围内观察到波动的半斯基尔米翁碎片,这归因于热激活的跳跃.
- 观察到一个不平衡的拓电荷,正电荷在较高的温度下占主导地位,负电荷在较低的温度下出现,因为 skyrmions 凝结.
结论:
- 纳米尺度的限制显著改变了奇拉性阴性液晶中的 skyrmion 动力学,导致波动减慢和新的碎片行为.
- 热激活的跳跃解释了半斯基尔米翁碎片的形成和动态.
- 取决于温度的拓电荷不平衡提供了关于 skyrmions 的凝结过程的见解.
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