An Analytical Quantum Model to Calculate Fluorescence Enhancement of a Molecule in Vicinity of a Sub-10 nm Metal Nanoparticle

An analytical quantum model is used to calculate electrical permittivity of a metal nanoparticle located in an adjacent molecule. Different parameters, such as radiative and non-radiative decay rates, quantum yield, electrical field enhancement factor, and fluorescence enhancement are calculated by such a model and they are compared with those obtained by using the classical Drude model. It is observed that using an analytical quantum model presents a higher enhancement factor, up to 30%, as compared to classical model for nanoparticles smaller than 10 nm. Furthermore, the results are in better agreement with those experimentally realized.

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Interplay between absorption and radiative decay rates of surface plasmon polaritons for field enhancement in periodic arrays

Optics Letters ◽

10.1364/ol.39.000501 ◽

2014 ◽

Vol 39 (3) ◽

pp. 501 ◽

Cited By ~ 7

Author(s):

ZhaoLong Cao ◽

Lei Zhang ◽

Chung-Yu Chan ◽

Hock-Chun Ong

Keyword(s):

Surface Plasmon ◽

Surface Plasmon Polaritons ◽

Radiative Decay ◽

Field Enhancement ◽

Decay Rates ◽

Periodic Arrays ◽

Plasmon Polaritons

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Decay Rates of Plasmonic Elliptical Nanostructures via Effective Medium Theory

Nanomaterials ◽

10.3390/nano11081928 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1928

Author(s):

Mohammed Gamal ◽

Ishac Kandas ◽

Hussein Badran ◽

Ali Hajjiah ◽

Mufasila Muhammed ◽

...

Keyword(s):

Decay Rate ◽

Radiative Decay ◽

Effective Medium Theory ◽

Field Enhancement ◽

Effective Medium ◽

Decay Rates ◽

Plasmonic Nanostructures ◽

Medium Theory ◽

Aspect Ratios ◽

Sensing Applications

This paper investigates the spontaneous decay rate of elliptical plasmonic nanostructures. The refractive index was analyzed using the effective medium theory (EMT). Then, the polarizability, spontaneous radiative, non-radiative decay rate, and electric field enhancement factor were characterized for the targeted elliptical nanostructures at different aspect ratios. All of the optical analyses were analyzed at different distances between the excited fluorescent coupled atom and the plasmonic nanostructure (down to 100 nm). This work is promising in selecting the optimum elliptical nanostructure according to the required decay rates for optical conversion efficiency control in energy harvesting for solar cells and optical sensing applications.

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Radiative decay rates in LaF3:Dy3+

Chemical Physics Letters ◽

10.1016/0009-2614(79)80463-7 ◽

1979 ◽

Vol 63 (1) ◽

pp. 90-92 ◽

Cited By ~ 2

Author(s):

H. Jagannath ◽

A. Sivaram ◽

D. Ramachandra Rao ◽

P. Venkateswarlu

Keyword(s):

Radiative Decay ◽

Decay Rates

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A New Thermionic Cathode Based on Carbon Nanotubes with a Thin Layer of Low Work Function Barium Strontium Oxide Surface Coating

MRS Proceedings ◽

10.1557/proc-1142-jj15-41 ◽

2008 ◽

Vol 1142 ◽

Author(s):

Feng Jin ◽

Yan Liu ◽

Scott A Little ◽

Chris M Day

Keyword(s):

Work Function ◽

Current Density ◽

Enhancement Factor ◽

Thermionic Emission ◽

Field Enhancement ◽

Oxide Coating ◽

Emission Current Density ◽

Emission Current ◽

Strontium Oxide ◽

Barium Strontium

ABSTRACTWe have created a thermionic cathode structure that consists of a thin tungsten ribbon; carbon nanotubes (CNTs) on the ribbon surface; and a thin layer of low work function barium strontium oxide coating on the CNTs. This oxide coated CNT cathode was designed to combine the benefits from the high field enhancement factor from CNTs and the low work function from the emissive oxide coating. The field emission and thermionic emission properties of the cathode have been characterized. A field enhancement factor of 266 and a work function of 1.9 eV were obtained. At 1221 K, a thermionic emission current density of 1.22A/cm2 in an electric field of 1.1 V/μm was obtained, which is four orders of magnitude greater than the emission current density from the uncoated CNT cathode at the same temperature. The high emission current density at such a modest temperature is among the best ever reported for an oxide cathode.

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