A Numerical Study of Absorption by Multilayered Biperiodic Structures

Ultra-broadband strong light absorption based on thin multilayered metamaterials

Light absorption plays an important role in many research areas. Here, we propose and demonstrate a thin ultra-broadband strong light absorber consisting of periodic taper arrays on a gold substrate.

Design of Tunable Biperiodic Graphene Metasurfaces

Periodic structures with subwavelength features are instrumental in the versatile and effective control of electromagnetic waves from radio frequencies up to optics. In this paper, we theoretically evaluate the potential applications and performance of electromagnetic metasurfaces made of periodically patterned graphene. Several graphene metasurfaces are presented, thereby demonstrating that such ultrathin surfaces can be used to dynamically control the electromagnetic wave reflection, absorption, or polarization. Indeed, owing to the graphene properties, the structure performance in terms of …

Application of metasurface description for multilayered metamaterials and an alternative theory for metamaterial perfect absorber

We analyze single and multilayered metamaterials by modeling each layer as a metasurface with effective surface electric and magnetic susceptibility derived through a thin film approximation. Employing a transfer matrix method, these metasurfaces can be assembled into multilayered metamaterials to realize certain functionalities. We demonstrate numerically that this approach provides an alternative interpretation of metamaterial-based perfect absorption, showing that the underlying mechanism is a modified Fabry-Perot resonance. This method provides a general approach applicable for decoupled o…

Stable Calculation of Optical Properties of Large Non-Periodic Dissipative Multilayered Systems

The calculation of the transfer matrix for a large non-periodic multilayered system may become unstable in the presence of absorption. We discuss the origin of this instability and we explore two methods to overcome it: the use of a total matrix to solve for all the fields at all the interfaces simultaneously and an expansion in the Bloch-like modes of a periodic artificially repeated system. We apply both methods to obtain the reflectance spectra of multilayered chirped structures composed of nanostructured porous silicon (PS). Both methods yield reliable and numerically stable results. The f…

介电体板中的相干虚拟吸收：对称与非对称几何结构的时域分析

Coherent Virtual Absorption in Dielectric Slabs: A Temporal Analysis of Symmetric and Asymmetric Geometries

本文研究了介电体板中相干虚拟吸收现象，通过时间域分析和频谱滤波方法，探讨了对称与非对称几何结构中的能量存储机制及复频动态应用。

Anomalous Light Transport Induced by Deeply Subwavelength Quasiperiodicity in Multilayered Dielectric Metamaterials

For dielectric multilayered metamaterials, the effective-parameter representation is known to be insensitive to geometrical features occurring at deeply subwavelength scales. However, recent studies on periodic and aperiodically ordered geometries have shown the existence of certain critical parameter regimes where this conventional wisdom is upended, as the optical response of finite-size samples may depart considerably from the predictions of standard effective-medium theory. In these regimes, characterized by a mixed evanescent/propagating light transport, different classes of spatial (dis)…