Study of plasmonics in hybrids made from a quantum emitter and double metallic nanoshell dimer

Abstract

We developed a theory for the fluorescence (FL) for quantum emitter and double metallic nanoshell dimer hybrids using the density matrix method. The dimer is made from two identical double metallic nanoshells, which are made of a dielectric core, a gold metallic shell and a dielectric spacer layer. The quantum emitters are deposited on the surface of the spacer layers of the dimers due to the electrostatic absorptions. We consider that dimer hybrids are surrounded by biological cells. This can be achieved by injecting them into human or animal cells. The surface plasmon polaritons (SPP) are calculated for the dimer using Maxwell's equations in the static wave approximation. The calculated SPP energy agrees with experimental data from Zhai et al (2017 Plasmonics 12 263) for the dimer made from a silica core, a gold metallic nanoshell and a silica spacer layer. We have also obtained an analytical expression of the FL using the density matrix method. We compare our theory with FL experimental data from Zhai et al (2017 Plasmonics 12 263) where the FL spectrum was measured by varying the thickness of the spacer layer from 9 nm to 40 nm. A good agreement between theory and experiment is found. We have shown that the enhancement of the FL increases as the thickness of the spacer layer decreases. We have also found that the enhancement of the FL increases as the distance between the double metallic nanoshells in the dimer decreases. These are interesting findings which are consistent with the experiments of Zhai et al (2017 Plasmonics 12 263) and can be used to control the FL enhancement in the FL-based biomedical imaging and cancer treatment. These interesting findings may also be useful in the fabrication of nanosensors and nanoswitches for applications in medicine.

Enhancement of Radiative and Nonradiative Emission in Random Lasing Plasmonic Nanofibers

“…With the help of refs. [ 30–32 ] the expressions of SPP and DDI fields are calculated as …”

“…In the above expression, we have considered because when the probe frequency is in resonance with the SPP frequency, the has a very large value. [ 30,31 ] In the derivation of Equation (9), we have also approximated if we put .…”

“…Recently, SPPs in MNPs have been widely studied in plasmonic literature. [ 24–31 ] In Section 1, we surveyed the literature for random lasers and nanofiber hybrids. In Section 2, the effect of the SPP and DDI is investigated on the bound photons in plasmonic nanofibers.…”

Study of ultrafast Rabi flopping in colloidal quantum dots at room temperature

“…The results showed that the two-photon fluorescence spectrum split from one peak to three peaks due to dressed states created in the system by strong DDIs 20 . Other similar researches have been done on hybrid materials with quantum dots or other quantum emitters 21,22 .…”

Harmonic Resonance Enhanced Second-Harmonic Generation in the Monolayer WS2–Ag Nanocavity

“…The induced quadrupole moment produces the SPP quadrupole electric field. The field can be calculated using the quasi-static approximation. − Let E QP cube be the electric fields produced by the quadrupole moment. By solving the Maxwell equations in the static wave approximation, the electric field produced by the Ag nanocube is calculated as where r c is the distance between the center of Ag nanocube and the center of the QE, and V cube is the volume of the nanocube, and function ζ QP cube is called the polarizability factors and depends on the shape of the Ag nanocube.…”