Dipolar Resonance Enhancement and Magnetic Resonance in Cross-Coupled Bow-Tie Nanoantenna Array by Plasmonic Cavity

Abstract

We experimentally demonstrate a simple approach for surface current engineering in a cross-coupled bow-tie nanoantenna by inserting a plasmonic cavity that simultaneously offers (i) improved Fano-like dipolar resonance contrast, (ii) electrically induced magnetic resonance, and (iii) enhanced sensitivity. By introducing a small geometric perturbation, we propose two physical parameters, offset (f) and split gap (s), for strong modulation of resonance location and intensity. We report at least 3.75-fold better dipolar resonance compared with the conventional design and demonstrate a unique mechanism for exciting magnetic plasmonic resonance. Finally, we obtain a large wavelength shift of 777.5 and 904 nm per refractive index unit (RIU) with a thin PMMA coating (110 nm) for the dipolar resonance and magnetic resonance, respectively. Numerical study indicates the potential of the proposed bow-tie nanoantenna array structure with a selfsimilar plasmonic cavity (SSP BNA) for sensitive recording of binding events of molecules such as DNA by reestablishing conduction current and providing "on" and "off" states. The high-density plasmonic antenna array structure will be promising for engineering applications in optical magnetism, magnetoplasmonics, optical trapping, and massively parallel ultrasensitive differential detection of molecular fingerprints.

Leveraging of MEMS Technologies for Optical Metamaterials Applications

“…The thin films of poly‐methyl methacrylate (PMMA) and ODT are the common analytes to characterize metamaterials sensing performance because they hold obvious fingerprints and are easy to functionalize on metamaterials resonator. During the last 10 years, many works were published utilizing various thin films of protein, lipid, DNA, and other biomolecular analytes . To overcome the limited detection of metamaterial resonators in the mid‐IR fingerprint region, Tittl et al proposed a hyperspectral imaging system using all‐dielectric metamaterial sensor array by varying the resonance wavelength of each sensor pixel, which enables bar‐code identification of molecules.…”

High Temperature Coupling of IR Inactive CC Mode in Complementary Metal Oxide Semiconductor Metamaterial Structure

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realizing the aforementioned applications in a broad wavelength range starting from the visible to microwave spectrum. [15][16][17][18][19][20][21][22][23][24][25][26] However, large scale application of plasmonic metamaterial is strongly dependent on both the scalability and repeatability of the fabrication process which can be reasonably ensured in CMOS technology. [15][16][17][18][19][20][21][22][23][24][25][26] However, large scale application of plasmonic metamaterial is strongly dependent on both the scalability and repeatability of the fabrication process which can be reasonably ensured in CMOS technology.

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“…[7][8][9][10][11][12][13][14] Thanks to the pioneering role of nanotechnology, complicated plasmonic architectures with multifunctionalities have been already demonstrated. [15][16][17][18][19][20][21][22][23][24][25][26] However, large scale application of plasmonic metamaterial is strongly dependent on both the scalability and repeatability of the fabrication process which can be reasonably ensured in CMOS technology. Very recently, CMOS fabricated designer optical structures have been reported to achieve high Q Fabry-Pérot resonance for gas sensing, [27,28] MEMS tunable metamaterials for terahertz communication, [29,30] and switchable mid-IR absorber [31] while relying on a fairly challenging process flow.…”

Thermoplasmonic Study of a Triple Band Optical Nanoantenna Strongly Coupled to Mid IR Molecular Mode

“…In the last few decades, the field of plasmonics received extensive attention of the researchers because of plasmon’s unprecedented ability to couple free space electromagnetic excitation into nanoscale volume and manipulate light-matter interaction. With the recent advancement of nanotechnology, plasmonics has become the emerging research topic in energy harvesting, telecom and sensing industries 6 7 8 9 10 11 . The plasmonic approach for probing thermal effect typically involves the observation of optical index variation in the surrounding as a function of temperature based on the far field optical measurement.…”