在光子微链网格中的拓方位节点半金属
Zihe Gao1, Haoqi Zhao2, Tianwei Wu3
1Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA. zihegao@seas.upenn.edu.
Nature communications
|June 2, 2023
概括
研究人员创造了一种具有二次节点的新型光子拓半金属,实现了继石墨烯之后的第二个最小的拓配置. 这一突破使得独特的奇拉粒子传输和同时进行克莱恩和反克莱恩道.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 拓学材料 拓学材料
- 光子学 是一个光子学.
背景情况:
- 石墨烯表现出最小的拓节点配置与迪拉克点.
- 高阶拓性半金属具有丰富的奇拉物理和装置潜力.
- 光子系统是拓现象的新兴平台.
研究的目的:
- 在光子微链网中实验实现具有二级节点的拓半金属.
- 为了研究混合性粒子中大质量和无质量元件的共存.
- 展示独特的运输特性,包括同时进行克莱恩和反克莱恩道.
主要方法:
- 一个光子微光网格的制造.
- 在Brillouin区域中心和边界的拓节点的表征.
- 对粒子运输现象的直接成像.
主要成果:
- 在Brillouin区域中心实验实现了强大的二次方程节点.
- 在Brillouin区域边界观察两个迪拉克点,形成第二个最小的拓配置.
- 展示了由于混合性奇拉粒子动态的同时克莱恩和反克莱恩道的演示.
结论:
- 光子微光网格成功地容纳了一个更高阶的拓半金属.
- 观察到的现象证实了尼尔森-尼诺米亚定理在这个光子系统.
- 这项工作为下一代具有新型传输特性的集成光子设备铺平了道路.
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