Analytical Approach to the Surface Plasmon Resonance Characteristic of Metal Nanoparticle Dimer in Dipole-Dipole Approximation

Kheirandish, Asef; Javan, N. Sepehri; Mohammadzadeh, Hosein

doi:10.1007/s11468-020-01198-4

“…The motivation of this work is finding analytical expressions for the permittivity of each MNP in a chain containing countable numbers of particles. Such an attempt for MNP dimer was successful in our recent work 27 where findings were in the agreement with experimental data. In the linear regime, the measurable parameter which is a complicated function of the permittivity is the extinction cross section of particles which indicates the absorption and scattering of light, thus, we calculate it for each MNP of chain.…”

Section: Introductionsupporting

confidence: 65%

Linear optical properties of a linear chain of interacting gold nanoparticles

Kheirandish,

Javan,

Mohammadzadeh

2021

Preprint

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In a Drude-like model for the conduction electrons of Metal Nanoparticles (MNPs) in a periodic linear chain, considering dipole-dipole interactions of adjacent particles, an analytical expression is derived for each particle permittivity for two different polarizations of incident light: parallel with and perpendicular to the chain line. A numerical analysis is carried out for a chain including 10 identical gold Nanoparticles (NPs) for two different sizes of NPs and two different host media of air and glass. It is shown that in the parallel case of polarization, interaction of NPs leads to a substantial increase in the extinction cross section and the red-shift of the Surface Plasmon Resonance (SPR) wavelength. In comparison with the linear properties of a single NP, the second and penultimate particles have the most increase in the extinction cross section and SPR wavelength displacement while the first and last particles experience the least variations due to the mutual interactions. For the perpendicular polarization, inversely, the dipolar coupling causes the decrease in extinction cross section of all particles and the blue-shift of SPR wavelength. For the parallel polarization, the absolute values of the real and imaginary parts of complex permittivity of each MNP decrease in comparison with the single particle case while they increase for the perpendicular state of polarization.

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“…The motivation of this work is finding analytical expressions for the permittivity of each MNP in a chain containing countable numbers of particles. Such an attempt for MNP dimer was successful in our recent work [27] where findings were in the agreement with experimental data. In the linear regime, the measurable parameter which is a complicated function of the permittivity is the extinction cross section of particles…”

supporting

confidence: 65%

“…in which the permittivity of the first and last particles reduces to the permittivity of MNP dimer obtained earlier in Ref. [27] and for other particles the extra coefficient of 2 shows the mutual interaction of each particle with two nearest neighbors.…”

Section: Modelsupporting

confidence: 50%

“…Also, the plasmon resonance wavelength places of all particles experienced red-shift in comparison with the air medium case, for example for the first and last NPs n = 1 and 10 which have the largest extinction, the plasmon wavelengths are 482.8nm and 509.9nm for air and glass media, respectively. It is worth mentioning that the dynamics of displacing plasmon resonance wavelength and its amplitude as well changes with the same fashion of MNP dimer case which has been investigated earlier experimentally [32][33][34] and theoretically [27]. 3), we increase the particle distances to g = 4R and plot the variations of extinction efficiency with respect to the wavelength for two different media and states of the incident light polarization.…”

Section: Numerical Discussionmentioning

confidence: 80%

“…The classical Thomson model [28] is employed to describe the interaction of EMW with conduction electrons of spherical MNP. Despite being unsuccessful in atomic physics for describing the atoms behavior, however this model still is recognized as an efficient approach for classical theories of the light-cluster interaction phenomena [1,27,29]. In this model, we suppose that the conduction electrons of N c individual metal atoms are homogeneously located inside the spherical volume of NP with radius a and the background positive ions which are distributed homogeneously as well, are immobile.…”

Section: Modelmentioning

confidence: 99%

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Linear optical properties of a linear chain of interacting gold nanoparticles

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In a Drude-like model for the conduction electrons of Metal Nanoparticles (MNPs) in a periodic linear chain, considering dipole-dipole interactions of adjacent particles, an analytical expression is derived for each particle permittivity for two different polarizations of incident light: parallel with and perpendicular to the chain line. A numerical analysis is carried out for a chain including 10 identical gold Nanoparticles (NPs) for two different sizes of NPs and two different host media of air and glass. It is shown that in the parallel case of polarization, interaction of NPs leads to a substantial increase in the extinction cross section and the red-shift of the Surface Plasmon Resonance (SPR) wavelength. In comparison with the linear properties of a single NP, the second and penultimate particles have the most increase in the extinction cross section and SPR wavelength displacement while the first and last particles experience the least variations due to the mutual interactions. For the perpendicular polarization, inversely, the dipolar coupling causes the decrease in extinction cross section of all particles and the blue-shift of SPR wavelength. For the parallel polarization, the absolute values of the real and imaginary parts of complex permittivity of each MNP decrease in comparison with the single particle case while they increase for the perpendicular state of polarization.

show abstract

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Histones are closely related to the state of chromatin, and epigenetic modification of their tail results in regulation in cells. Therefore, developing various analytical tools to map the changes in position and distribution of histone modifications is helpful in studying underlying mechanisms. Herein, we propose a high-spatial and colourimetric imaging method using plasmonic nanoparticles as probes to visualize heterochromatin histone markers in a single nucleus. We visualized the reorganization between repressive histone markers, H3K9me3 and H3K27me3, caused by oncogene-induced senescence based on the scattering colours and spectral shift of plasmonic nanoprobes to longer wavelengths using their distance-dependent coupling effect. The measured scattering profiles were correlated with the computation results simulating the scattering spectra according to the arrangements and distances among the plasmonic nanoprobes. The plasmonic nanoprobe-based high-spatial hyperspectral imaging provides an advanced way to study the dynamics of histone modifications for predicting the progression of diseases or senescence.

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Analytical Approach to the Surface Plasmon Resonance Characteristic of Metal Nanoparticle Dimer in Dipole-Dipole Approximation

Cited by 7 publications

References 46 publications

Linear optical properties of a linear chain of interacting gold nanoparticles

Linear optical properties of a linear chain of interacting gold nanoparticles

Linear optical properties of a linear chain of interacting gold nanoparticles

High-spatial and colourimetric imaging of histone modifications in single senescent cells using plasmonic nanoprobes

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