Optical quantum yield in plasmonic nanowaveguide

Abstract

We have developed a theory of the quantum yield for plasmonic nanowaveguide where the cladding layer is made of an ensemble of quantum dots and the core layer consists of an ensemble of metallic nanoparticles. The bound states of the confined probe photons in the plasmonic nanowaveguide are calculated using the transfer matrix method based on the Maxwell equations. It is shown that the number of bound states in the nanowaveguide depends on the dielectric properties of the core and cladding layers. The surface plasmon polaritons (SPPs) produced by the metallic nanoparticles interacts with the excitons of the quantum dots. The radiative and nonradiative linewidths of excitons in the quantum yield are calculated using the quantum mechanical perturbation theory. We have found that the quantum yield decreases as the dipole–dipole interaction between metallic nanoparticles increases. We have also calculated the photoluminescence and found that the enhancement in photoluminescence is due to the SPPs coupling. On the other hand, the quenching in the photoluminescence is due to the quantum yield. We compared our theory with experiments of a nanowaveguide where the core is fabricated from Ag- nanoparticles and the cladding is fabricated from the perovskite quantum dots. A good agreement between theory and experiments is found. Our analytical expressions of the quantum yield and photoluminescence can be used by experimentalists to proforma new types of experiments and for inventing new types of nanosensors and nanoswitches.

Tunable Narrowband Silicon-Based Thermal Emitter with Excellent High-Temperature Stability Fabricated by Lithography-Free Methods

“…This localized magnetic field distribution indicates the existence of a strong optical Tamm state in the interface, and then the strong density of optical Tamm state in this interface enhances the decay rates and causes the localized energy of incident light to be completely dissipated by the W layer into heat energy. [ 45 , 46 ] Correspondingly, the Si-W-SiN/SiNO structure can exhibit an excellent optical absorption performance around the resonance wavelength. Additionally, the localized energy of incident light dissipated by the W film indicates that the W film is really acting as the thermal radiation source when operating at high temperatures.…”

Controllable Excitation of Surface Plasmon Polaritons in Graphene‐Based Semiconductor Quantum Dot Waveguides

“…More accurate calculation of radiative and nonradiative linewidths of excitons in hybrid systems requires the use of successive derivation based on quantum mechanical perturbation theory. [44] At the same time, we consider the QDs as small defects that slightly change the kinetics of the propagating SPPs. Therefore, the dispersion equation for the SPP propagating in such a QD-loaded two graphene sheets waveguide can be considered as the dispersion equation for two graphene sheets waveguide without QDs written in the form [56] −k h…”

“…In this case, DDI can dominate on SPP generation, and energy transfer in such a waveguide with densely placed QDs occurs between QDs in the chain by means of DDI, and Equation ( 5) is not applicable. The study of such a regime requires the consistent consideration of the role of DDI between QDs [21,44] placed inside the waveguide in the condition of development of plasmonic-assistant effects, including nonlinear effects.…”

“…Note that the distances between individual QDs in the system are chosen to be the same order of magnitude or larger than the characteristic SPP wavelength in the system. Considerable reduction of such a distance can lead to an increase in the role of near-field dipole-dipole interaction (DDI) between nanoparticles (NPs) [42][43][44] and changing the regime from plasmonic waveguide to non-radiative energy transmission by means of photonic bound states. [45] In our investigation, we use a semiclassical approach to define the graphene waveguide system's main parameters with an Ag 2 Se QD array that can lead to the excitation of graphene SPPs only in the local space between the gold stripes used to connect external electrical voltages.…”

Enhanced Photoluminescence of Gold Nanoparticle‐Quantum Dot Hybrids Confined in Hairy Polymer Nanofibers

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