Hot Electron Plasmon-Resonant Grating Structures for Enhanced Photochemistry: A Theoretical Study

Metallic grating structures have been shown to provide an effective platform for generating hot electrons and driving electrochemical reactions. Here, we present a systematic theoretical study of the surface plasmon resonance in different corrugated metallic grating structures using computational electromagnetic tools (i.e., the finite difference time domain (FDTD) method). We identify the corrugation parameters that produce maximum resonant field enhancement at commonly used wavelengths for photocatalytic applications (633 nm and 785 nm) in different material systems, including Ag, Au, Cu, Al, and Pt. The absorption spectra of each grating structure have been fitted with the analytical equation obtained from Coupled Mode Theory. We then extracted the absorptive and radiative loss rates. The field enhancement can be maximized by matching the absorption and radiation losses via tuning the geometric parameters. We could improve the average field enhancement of 633 nm and 785 nm modes by a factor of 1.8× and 3.8× for Ag, 1.4× and 3.6× for Au, and 1.2× and 2.6× for Cu. The optimum structures are found to be shallower for Ag, Au, and Cu; deeper for Pt; and to almost remain the same for Al. The gratings become flat for all the metals for increasing the average field enhancement. Overall, Ag and Au were found to be the best in terms of overall field enhancement while Pt had the worst performance.

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Colloidal Plasmonic Nanostar Antennas with Wide Range Resonance Tunability

10.26434/chemrxiv.6552743 ◽

2019 ◽

Cited By ~ 1

Author(s):

Theodoros Tsoulos ◽

Supriya Atta ◽

Maureen Lagos ◽

Michael Beetz ◽

Philip Batson ◽

...

Keyword(s):

Single Particle ◽

Structural Complexity ◽

Field Enhancement ◽

Hot Electron ◽

Structure Property ◽

Plasmon Band ◽

Gold Nanostars ◽

Wide Range ◽

Particle Level ◽

Spectrally Resolved

<div>Gold nanostars display exceptional field enhancement properties and tunable resonant modes that can be leveraged to create effective imaging tags or phototherapeutic agents, or to design novel hot-electron based photocatalysts. From a fundamental standpoint, they represent important tunable platforms to study the dependence of hot carrier energy and dynamics on plasmon band intensity and position. Toward the realization of these platforms, holistic approaches taking into account both theory and experiments to study the fundamental behavior of these</div><div>particles are needed. Arguably, the intrinsic difficulties underlying this goal stem from the inability to rationally design and effectively synthesize nanoparticles that are sufficiently monodispersed to be employed for corroborations of the theoretical results without the need of single particle experiments. Herein, we report on our concerted computational and experimental effort to design, synthesize, and explain the origin and morphology-dependence of the plasmon modes of a novel gold nanostar system, with an approach that builds upon the well-known plasmon hybridization model. We have synthesized monodispersed samples of gold nanostars with finely tunable morphology employing seed-mediated colloidal protocols, and experimentally observed narrow and spectrally resolved harmonics of the primary surface plasmon resonance mode both at the single particle level (via electron energy loss spectroscopy) and in ensemble (by UV-Vis and ATR-FTIR spectroscopies). Computational results on complex anisotropic gold nanostructures are validated experimentally on samples prepared colloidally, underscoring their importance as ideal testbeds for the study of structure-property relationships in colloidal nanostructures of high structural complexity.</div>

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A Plasmonic Refractive-Index Sensor Based Multiple Fano Resonance Multiplexing in Slot-Cavity Resonant System

Photonic Sensors ◽

10.1007/s13320-021-0631-8 ◽

2021 ◽

Author(s):

Zicong Guo ◽

Kunhua Wen ◽

Yuwen Qin ◽

Yihong Fang ◽

Zhengfeng Li ◽

...

Keyword(s):

Fano Resonance ◽

Fdtd Method ◽

Rectangular Cavity ◽

Refractive Index Sensor ◽

Right Wing ◽

Left Wing ◽

Resonant System ◽

Coupled Mode ◽

Metal Insulator Metal ◽

The Right

AbstractIn this paper, a sub-wavelength metal-insulator-metal (MIM) waveguide structure is proposed by using a cross-shape rectangular cavity, of which wings are coupled with two rectangular cavities. Firstly, a cross-shape rectangular cavity is placed between the input and output MIM waveguides. According to the mutual interference between bright and dark modes, three Fano resonant peaks are generated. Secondly, by adding a rectangular cavity on the left wing of the cross shaped one, five asymmetric Fano resonance peaks are obtained. Thirdly, six asymmetric Fano resonance peaks are achieved after adding another cavity on the right wing. Finally, the finite-difference-time-domain (FDTD) method and multimode interference coupled-mode theory (MICMT) are used to simulate and analyze the coupled plasmonic resonant system, respectively. The highest sensitivity of 1 000nm/RIU is achieved.

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A Non-Equilibrium Approach to Coupled-Mode-Induced Hot-Electron Energy Loss Rate

Communications in Theoretical Physics ◽

10.1088/0253-6102/19/4/403 ◽

1993 ◽

Vol 19 (4) ◽

pp. 403-408

Author(s):

M.W. Wu ◽

X.L. Lei

Keyword(s):

Energy Loss ◽

Electron Energy ◽

Loss Rate ◽

Hot Electron ◽

Energy Loss Rate ◽

Coupled Mode ◽

Equilibrium Approach ◽

Electron Energy Loss ◽

Non Equilibrium

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Estimation of resonance characteristics of single-layer surface-plasmon sensors in liquid solutions using Fano’s approximation in the visible and infrared regions

Computer Optics ◽

10.18287/2412-6179-2019-43-4-596-604 ◽

2019 ◽

Vol 43 (4) ◽

pp. 596-604 ◽

Cited By ~ 4

Author(s):

D.V. Nesterenko ◽

R.A. Pavelkin ◽

S. Hayashi

Keyword(s):

Surface Plasmon ◽

Single Layer ◽

Field Enhancement ◽

Coupled Mode Theory ◽

Mid Infrared ◽

Coupled Mode ◽

Sensing Applications ◽

Resonance Response ◽

Liquid Solutions ◽

Support Excitation

In this work, we consider the use of planar sensing structures, which support excitation of surface plasmon polarition (SPP) modes, for detecting changes in solvents, i.e. water, ethanol, isopropanol. In the structures under study, SPP modes propagate along the interfaces between metals and general solvents. The analysis of characteristics of the resonance response is based on Fano’s approximation within the coupled-mode theory in the visible and infrared regions. The maximum sensitivity and field enhancement are revealed in the near- and mid-infrared regions in the case of ethanol and isopropanol, which enables sensing applications beyond the regions of water absorption.

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Transmission Properties of Metallic Grating with Subwavelength Slits in THz Frequency Region

Active and Passive Electronic Components ◽

10.1155/2007/63139 ◽

2007 ◽

Vol 2007 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Dong Liang ◽

Qirong Xing ◽

Zhen Tian ◽

Changlei Wang ◽

Weili Zhang ◽

...

Keyword(s):

Theoretical Study ◽

Wavelength Region ◽

Grating Period ◽

Frequency Region ◽

Incident Wavelength ◽

Long Wavelength ◽

Metallic Grating ◽

Transmission Properties ◽

And Control ◽

Good Agreement

This paper presents a fully experimental and theoretical study on transmission properties of a deep metallic grating with subwavelength slits in THz frequency region by using THz time domain spectroscopy (THz-TDS). The grating exposed top-polarized incident wave exhibits enhanced nonresonant transmission in the long-wavelength region where the incident wavelength is larger than the grating period. Wood anomalies are observed when the wavelength is comparable to the grating period. Strict theory is given to explain the experimental results and the two are in good agreement. It is proposed that the Wood dips may be considered a criterion and a tool to judge and control the uniformity or fabricating accuracy of the grating period.

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Hot Electron Driven Photocatalysis on Plasmon-Resonant Grating Nanostructures

ACS Applied Materials & Interfaces ◽

10.1021/acsami.0c00066 ◽

2020 ◽

Vol 12 (15) ◽

pp. 17459-17465 ◽

Cited By ~ 1

Author(s):

Yu Wang ◽

Indu Aravind ◽

Zhi Cai ◽

Lang Shen ◽

George N. Gibson ◽

...

Keyword(s):

Hot Electron ◽

Resonant Grating

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Manifestation of the spontaneous parity-time symmetry breaking phase transition in hot-electron photodetection based on a tri-layered metamaterial

Nanophotonics ◽

10.1515/nanoph-2018-0207 ◽

2019 ◽

Vol 8 (3) ◽

pp. 495-504 ◽

Cited By ~ 1

Author(s):

Qiang Bai

Keyword(s):

Phase Transition ◽

Theoretical Model ◽

Symmetry Breaking ◽

Pt Symmetry ◽

Coupled Mode Theory ◽

Hot Electron ◽

Electron Device ◽

Coupled Mode ◽

Time Symmetry ◽

Existence Conditions

AbstractWe theoretically and numerically demonstrate that the spontaneous parity-time (PT) symmetry breaking phase transition can be realized respectively by using two independent tuning ways in a tri-layered metamaterial that consists of periodic array of metal-semiconductor Schottky junctions. The existence conditions of PT symmetry and its phase transition are obtained by using a theoretical model based on the coupled mode theory. A hot-electron photodetection based on the same tri-layered metamaterial is proposed, which can directly show the spontaneous PT symmetry breaking phase transition in photocurrent and possesses dynamical tunability and switchability. This work extends the concept of PT symmetry into the hot-electron photodetection, enriches the functionality of the metamaterial and the hot-electron device, and has varieties of potential and important applications in optoelectronics, photodetection, photovoltaics, and photocatalytics.

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