Emerging Trends in Metamaterials and Metasurfaces Research

Dear Colleagues,

Metamaterials and metasurfaces are artificially structured materials crafted through the precise arrangement of metallic or dielectric inclusions, often organized in a periodic lattice. Crucially, the way these structures behave at the mesoscopic level is determined not only by the chemical composition of their constituent elements, but also by the specific geometric characteristics (size, shape, orientation, and more) of these elements. As a result, metamaterials and metasurfaces provide a multitude of design possibilities and, consequently, a wide range of physically attainable responses. These intricately engineered materials have the potential to yield unconventional and advantageous electromagnetic responses that extend beyond the capabilities of natural media. Their meticulous manipulation of electromagnetic fields and unprecedented control over electromagnetic wave propagation have positioned metamaterials and metasurfaces at the forefront of scientific research for over two decades. The objective of this Special Issue is to showcase the most current developments in metamaterial design and applications, with a focus on configurations offering advanced properties, versatile functionalities and intriguing applications. We invite you to submit a research paper on the theoretical aspects and/or practical applications of artificially structured media in this Special Issue of Photonics entitled “Emerging Trends in Metamaterials and Metasurfaces Research”.

We welcome submissions on topics that include (but not limited to) emerging trends on :

• Nonlinear metamaterials and metasurfaces;
• Reconfigurable and programmable (smart) metamaterials and metasurfaces;
• Spacetime-modulated structures;
• Metamaterials and metasurfaces for enhanced imaging capabilities;
• Active metamaterials and metasurfaces;
• Metamaterials and metasurfaces for biomedical applications;
• Metamaterials and metasurfaces for wavefront control;
• Topological metamaterials and metasurfaces;
• Extreme wave phenomena in metamaterials and metasurfaces；
• Metamaterial antennas and sensors.

Dr. David E. Fernandes
Dr. Tiago A. Morgado
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Photonics is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• nonlinear metamaterials and metasurfaces
• reconfigurable and programmable (smart) metamaterials and metasurfaces
• space-time modulated structures
• metamaterials and metasurfaces for enhanced imaging capabilities
• active metamaterials and metasurfaces
• metamaterials and metasurfaces for biomedical applications
• metamaterials and metasurfaces for wavefront control
• topological metamaterials and metasurfaces
• extreme wave phenomena in metamaterials and metasurfaces
• metamaterial antennas and sensors

Title: Optimized Wide-Angle Metamaterial Edge Filters: Enhanced Performance with Multi-Layer Designs and Anti-Reflection Coatings
Authors: Baidong Wu; James N Monks; Liyang Yue; Andrew Hurst; Zengbo Wang
Affiliation: School of Computer Science and Engineering, Bangor University, Dean Street, Bangor, Gwynedd, LL57 1UT, UK;
Abstract: This study presents a systematic optimization of wide-angle metamaterial long-pass (LP) edge filters based on silicon nanospheres (SiNP). Multi-layered configurations incorporating SiNP-meta-films and anti-reflection coatings (ARC) elements not previously considered in the literature are explored to enhance filter performance in both stop and pass-bands. The research has successfully developed an accurate model for the effective refractive index using the Kramers-Kronig relations, enabling the use of classical thin-film design software for rapid device performance optimization, which is verified by full-wave numerical software. This systematic optimization has produced highly efficient, near-shift-free long-pass metamaterial filters, evidenced by their high optical density (OD = 2.55) and low spectral shift across a wide angular range (0°–60°). This systematic optimization has yielded long-pass metamaterial filters with the highest optical density (OD = 2.55, 0.28%) among metamaterial-based counterparts, with a minimal spectral shift up to 60°. These advancements herald the development of high-efficiency metamaterial optical components suitable for a variety of applications that require consistent performance across diverse angles of incidence.