在光子准晶体中增强了混乱的传输
Liad Levi1, Mikael Rechtsman, Barak Freedman
1Department of Physics and Solid State Institute, Technion, Haifa, Israel.
概括
障碍可以增强准晶体中的波传输,导致光束膨胀和在安德森定位之前的扩散式传输. 这挑战了对扰乱对波传播影响的传统理解.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 波浪现象是一种波浪现象.
背景情况:
- 准晶体表现出独特的无周期结构,具有禁止的旋转对称性.
- 障碍通常会抑制周期性和非周期性介质中的波传输.
- 了解复杂结构中的波传输对于材料设计至关重要.
研究的目的:
- 通过实验观察和描述混乱对准晶体中波浪传输的影响.
- 为了调查从混乱增强运输到安德森定位的过渡.
- 阐明这些现象在半晶体介质中的根本起源.
主要方法:
- 使用光子半晶体进行的实验.
- 准晶体介质中障碍水平的系统变化.
- 测量光束传播以分析运输特征.
主要成果:
- 观察到混乱增强的波传输,导致光束扩张的增加.
- 确定了一个扩散式的运输模式,随着越来越多的混乱.
- 证明过渡到安德森局部化,并抑制了更高的障碍水平的传输.
结论:
- 障碍可以意外地增强准晶体中的波传输,这与传统的预期相反.
- 这项研究揭示了扰乱和准晶体结构之间影响波传播的复杂相互作用.
- 这些发现为混乱的无周期系统中的波动力学提供了新的见解.
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