{"title":"Si3N4 Dielectric Hemi-sphere Arrayed Plasmonic Metasurface With Top Metal Coating for Multiresonant Absorption in NIR Regime","authors":"Prasanta Mandal","doi":"10.1007/s11468-024-02427-w","DOIUrl":null,"url":null,"abstract":"<p>Present report focuses on the design and optical perfect absorption/reflection properties of novel plasmonic metasurface made of square array of Si<sub>3</sub>N<sub>4</sub> hemi-spheres on flat Si<sub>3</sub>N<sub>4</sub> surface. The whole structure is sandwiched between flat gold layer and top gold coating. Theoretical study using Finite Difference Time Domain (FDTD) computation shows multiple near perfect absorptions (80–100%) with narrow line width (~ 50 nm) between 550 to 1500 nm. Four distinct absorption peaks (or reflection dips) are observed at 1020 nm (A1), 888 nm (A2), 614 nm (A3), 740 nm (A4) which can be manipulated by varying structural parameters such as period, hemi-sphere diameter and top gold coating thickness. These multiple absorptions arise due to electric dipolar resonance, magnetic resonance, excitation of various surface plasmon modes (such as (1,0); (2,0); (1,1)) and cavity mode, as evident from near-field analysis. With appropriate structural parameters, multiband well resolved near perfect absorptions are achieved at desired wavelengths. The proposed metasurface is insensitive to the polarization of excitation beam, and has relatively large launch angle tolerance (~ 20°), making it suitable for optical and optoelectronic device integration.</p>","PeriodicalId":736,"journal":{"name":"Plasmonics","volume":"26 1","pages":""},"PeriodicalIF":3.3000,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasmonics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1007/s11468-024-02427-w","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Present report focuses on the design and optical perfect absorption/reflection properties of novel plasmonic metasurface made of square array of Si3N4 hemi-spheres on flat Si3N4 surface. The whole structure is sandwiched between flat gold layer and top gold coating. Theoretical study using Finite Difference Time Domain (FDTD) computation shows multiple near perfect absorptions (80–100%) with narrow line width (~ 50 nm) between 550 to 1500 nm. Four distinct absorption peaks (or reflection dips) are observed at 1020 nm (A1), 888 nm (A2), 614 nm (A3), 740 nm (A4) which can be manipulated by varying structural parameters such as period, hemi-sphere diameter and top gold coating thickness. These multiple absorptions arise due to electric dipolar resonance, magnetic resonance, excitation of various surface plasmon modes (such as (1,0); (2,0); (1,1)) and cavity mode, as evident from near-field analysis. With appropriate structural parameters, multiband well resolved near perfect absorptions are achieved at desired wavelengths. The proposed metasurface is insensitive to the polarization of excitation beam, and has relatively large launch angle tolerance (~ 20°), making it suitable for optical and optoelectronic device integration.
期刊介绍:
Plasmonics is an international forum for the publication of peer-reviewed leading-edge original articles that both advance and report our knowledge base and practice of the interactions of free-metal electrons, Plasmons.
Topics covered include notable advances in the theory, Physics, and applications of surface plasmons in metals, to the rapidly emerging areas of nanotechnology, biophotonics, sensing, biochemistry and medicine. Topics, including the theory, synthesis and optical properties of noble metal nanostructures, patterned surfaces or materials, continuous or grated surfaces, devices, or wires for their multifarious applications are particularly welcome. Typical applications might include but are not limited to, surface enhanced spectroscopic properties, such as Raman scattering or fluorescence, as well developments in techniques such as surface plasmon resonance and near-field scanning optical microscopy.