Admittance spectra of silicon photocells: from dark mode to weak illuminate mode

AbstractRaman optical activity (ROA) is effective for studying the conformational structure and behavior of chiral molecules in aqueous solutions and is advantageous over X-ray crystallography and nuclear magnetic resonance spectroscopy in sample preparation and cost performance. However, ROA signals are inherently minuscule; 3–5 orders of magnitude weaker than spontaneous Raman scattering due to the weak chiral light–matter interaction. Localized surface plasmon resonance on metallic nanoparticles has been employed to enhance ROA signals, but suffers from detrimental spectral artifacts due to its photothermal heat generation and inability to efficiently transfer and enhance optical chirality from the far field to the near field. Here we demonstrate all-dielectric chiral-field-enhanced ROA by devising a silicon nanodisk array and exploiting its dark mode to overcome these limitations. Specifically, we use it with pairs of chemical and biological enantiomers to show >100x enhanced chiral light–molecule interaction with negligible artifacts for ROA measurements.

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Grating induced transparency (GIT) and the dark mode in optical waveguides

Optics Express ◽

10.1364/oe.17.011710 ◽

2009 ◽

Vol 17 (14) ◽

pp. 11710 ◽

Cited By ~ 27

Author(s):

Hsi-Chun Liu ◽

Amnon Yariv

Keyword(s):

Optical Waveguides ◽

Dark Mode ◽

Induced Transparency

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Tunable asymmetric mode conversion using the dark-mode of three-mode waveguide system

Optics Express ◽

10.1364/oe.22.028683 ◽

2014 ◽

Vol 22 (23) ◽

pp. 28683 ◽

Cited By ~ 6

Author(s):

Joonsoo Kim ◽

Seung-Yeol Lee ◽

Yohan Lee ◽

Hwi Kim ◽

Byoungho Lee

Keyword(s):

Mode Conversion ◽

Dark Mode ◽

Asymmetric Mode ◽

Waveguide System

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Dual-Tunable Polarization Insensitive Electromagnetically Induced Transparency in Metamaterials

Journal of Electronic Materials ◽

10.1007/s11664-020-08692-9 ◽

2021 ◽

Author(s):

Renxia Ning ◽

Zhiqiang Xiao ◽

Zhenhai Chen ◽

Wei Huang

Keyword(s):

Vanadium Dioxide ◽

Mode Coupling ◽

Slow Light ◽

Chemical Potential ◽

Electromagnetically Induced Transparency ◽

Dark Mode ◽

Potential Applications ◽

Polarization Insensitive ◽

Terahertz Devices ◽

Induced Transparency

AbstractA multilayer structure of a square ring of graphene with nesting vanadium dioxide (VO2) was investigated in this study. This structure exhibits electromagnetically induced transparency (EIT), which stems from a bright mode coupling with a dark mode. The permittivity values of graphene and VO2 can be modulated via chemical potential and temperature, respectively. The EIT effect can be tuned based on the chemical potential of graphene and temperature of VO2, resulting in a dual-tunable EIT effect. Simulation results confirmed that this dual-tunable EIT phenomenon is insensitive to polarization. These results may have potential applications in terahertz devices, such as slow light devices, switching devices, and sensors.

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Plasmons Coupling and Anti-Crossing of Nanometal Asymmetric Dimer

10.21203/rs.3.rs-162249/v1 ◽

2021 ◽

Author(s):

Jianxin Zhang ◽

Jian Zhang ◽

Yongfang Li

Keyword(s):

Harmonic Oscillator ◽

Electrostatic Potential ◽

Physical Mechanism ◽

Coupling Model ◽

Frequency Offset ◽

Plasmon Coupling ◽

Dark Mode ◽

Harmonic Oscillator Model ◽

Asymmetric Dimer ◽

Bright Mode

Abstract In this paper, by defining a new physical quantity called as the frequency offset in the harmonic oscillator model and combining with the established plasmon coupling model, we successfully explain the anti-crossing property caused by plasmon coupling of dimer composed of a silver nanoring and a silver nanorod. In the plasmons coupling model, we reasonably reveal that the physical mechanism of the coupling between bright mode and dark mode of the plasmons is mainly represented by the coulomb potential and the electrostatic potential. With this model, we explain also the asymmetric feature the variation of frequency offset and coupling coefficient with coupling distance.

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