连续体中的复杂带结构和有限状态:一个统一的理论框架
Jie Liu1, Ziyun Peng1, Qianju Song2
1Chongqing University, School of Physics, Chongqing University, Chongqing 401331, China, Chongqing, 400044, China.
概括
本研究引入了一种第一原理方法来计算周期介质的复杂波段结构,揭示了光束现象,如连续体中的束状态 (BIC) 和异常点 (EP). 该方法系统地分析散射矩阵通道和布洛赫波相互作用,以准确预测.
科学领域:
- 光学和光子学 在光学和光子学.
- 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
背景情况:
- 波段结构分析对于理解周期介质中的波传播至关重要.
- 像光子晶体 (PhC) 板这样的开放系统由于能量泄漏而面临挑战.
- 使用非赫米特汉密尔顿的现有方法依赖于手动模式选择,并且可能遭受基础不完整.
研究的目的:
- 开发一种系统的第一原则方法来推导开放周期系统中的复杂波段结构.
- 阐明现象背后的物理机制,比如连续体中的有限状态 (BIC) 和异常点 (EP).
- 为研究复杂的带结构和光限制提供统一的框架.
主要方法:
- 在散射矩阵中确定最小的通道,基于散发的批量布洛赫波.
- 分析这些布洛赫波之间的相互作用,揭示了复杂的带结构.
- 结合直角偏振波来表征远场偏振和EPs.
主要成果:
- 两个布洛赫波可以预测前级的想象频率,并识别意外的BIC.
- 三个布洛赫波揭示了强大的弗里德里希-温特根和对称性保护的BIC,以及线宽行为.
- 该框架准确地预测想象频率,包括所有已知的BIC,并在2D周期结构中跟踪它们的参数演变.
结论:
- 提出的第一原则方法为研究周期性介质中的复杂带结构提供了一个统一的基础.
- 这种方法系统地揭示了BIC和EP等现象,而不依赖于手动模式选择.
- 促进了在开放周期系统中更深入地探索光束束和波传播.
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