论文标题
连续体中超级准绑定的状态
Super quasi-bound state in the continuum
论文作者
论文摘要
避免了共振的交叉并合并连续体（BIC）中的多个绑定状态是定制BICS物理特性的平行手段。本文中，我们引入了一个新的超级准比例概念，用于光子晶体（PHC）系统，其中其质量（$ q $）因子在参数和动量空间中都得到了增强。通过避免在参数空间中避免了两个对称性保护（SP）准BIC，并同时将BICS合并在动量空间中，可以在有限的PHC中实现具有大量增强$ Q $因子的超级准BIC。更重要的是，分析理论表明，所提出的机制导致$ q $因子的渐近行为超过谐振器的渐近行为，从$ n^2 $到SP-BICS的独家$ n^3 $，这对于在紧凑型PHC中实现准BICS至关重要。进行微波实验以验证理论结果。我们的结果为操纵有限PHC结构中的物理特性的物理特性提供了范式转移，这将促进各种应用，包括但不限于低阈值激光，无线功率传递和高功绩感测等图等。
Avoided crossing of resonances and merging multiple bound states in the continuum (BICs) are parallel means for tailoring the physical properties of BICs. Herein, we introduce a new concept of super quasi-BIC for photonic crystal (PhC) systems where its quality ($Q$) factor is boosted in both parametric and momentum spaces. A super quasi-BIC with substantial enhancement of $Q$ factor can be achieved in a finite PhC by combining avoiding crossing of two symmetry protected (SP) quasi-BICs in parametric space and merging BICs in momentum space simultaneously. More importantly, analytical theory shows that the proposed mechanism results in the transition of asymptotic behavior of the $Q$ factor over the numbers of resonators from $N^2$ to exclusive $N^3$ for SP-BICs, which is of vital importance for realizing quasi-BICs in a compact PhC. Microwave experiments are performed to validate the theoretical results. Our results provide a paradigm shift for manipulating the physical properties quasi-BICs in finite PhC structures, which would facilitate various applications, including but not limited to low threshold lasing, wireless power transfer and high figure of merit sensing etc.
