arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2003.04596physics.optics
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带基底的纳米粒子晶格:傅里叶模态方法和偶极子近似

Nanoparticle lattices with bases: Fourier modal method and dipole approximation

I. M. Fradkin, S. A. Dyakov, N. A. Gippius

摘要:

周期性结构(例如光子晶体和超颖表面)的利用对于纳米尺度的光操纵是常见的。基于电磁场傅立叶分解的傅立叶模态方法(FMM)是考虑它们并设计有效光学器件的最广泛使用的计算方法之一。然而,计算周期性结构与小夹杂物往往是一项困难的任务,因为他们诱导大量的高- $k_\parallel$谐波,应该考虑。本文考虑了带基底的小粒子格,并利用离散偶极子近似(DDA)构造了它们的散射矩阵。然后,考虑到复杂的分层结构,这些矩阵在FMM中实现。我们所提出的混合方法的性能,它的应用程序的晶格,路由左,右圆偏振入射光的导模在相反的方向传播。我们还证明了它的精度与有限元法(FEM)计算的频谱比较。这种方法的高速度和高精度使得能够在合理的时间内以非常高的分辨率计算角度相关光谱,这使得能够分辨其他方法无法观察到的窄线。

英文摘要:

The utilization of periodic structures such as photonic crystals and metasurfaces is common for light manipulation at nanoscales. One of the most widely used computational approaches to consider them and design effective optical devices is the Fourier modal method (FMM) based on Fourier decomposition of electromagnetic fields. Nevertheless, calculating of periodic structures with small inclusions is often a difficult task, since they induce lots of high-$k_\parallel$ harmonics that should be taken into account. In this paper, we consider small particle lattices with bases and construct their scattering matrices via discrete dipole approximation (DDA). Afterwards, these matrices are implemented in FMM for consideration of complicated layered structures. We show the performance of the proposed hybrid approach by its application to a lattice, which routes left and right circularly polarized incident light to guided modes propagating in opposite directions. We also demonstrate its precision by spectra comparison with finite element method (FEM) calculations. The high speed and precision of this approach enable the calculation of angle-dependent spectra with very high resolution in a reasonable time, which allows resolving narrow lines unobservable by other methods.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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