Enhancement of Radiative and Nonradiative Emission in Random Lasing Plasmonic Nanofibers

Abstract

A theory of light–matter interaction in plasmonic nanofibers is developed. When probe light propagates inside the nanofiber, it induces surface plasmon polariton (SPPs) and electric dipoles in metallic nanoparticles. The dipoles interact with each other via dipole–dipole interaction (DDI). The energy of photonic bound states in the presence of the SPP and DDI fields are calculated. It has been demonstrated that the number of bound states can be controlled by the strength of SPP and DDI couplings. The spontaneous decay rate for the quantum emitters have been calculated and it is found that decay rate is enhanced when the exciton energy is in resonance with the bound photon energy. Further, it is predicted that the spontaneous decay rate also enhances when the exciton and SPP energies are in resonance. Finally, the photoluminescence in nanofiber is calculated using the density matrix method. The authors' theory is compared with experiments and found a good agreement between theory and experiments. It has been demonstrated that the quenching of the photoluminescence intensity increases as the concentration of the MNPs increases. The findings of the paper can be used to fabricate random lasers and also 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.…”

Transient Study of Photoluminescence in Nanowaveguides Doped with Quantum Emitters and Metallic Nanoparticles

“…Three electric fields (i. e., probe, SPP and DDI electric fields) are present in the waveguide. Following the method of reference, [34] the dispersion relation of propagating photons in the core region of the nanowaveguide is written as [34] $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr k^2 = F_c^2 (\varepsilon _k )\begin{matrix}, & {F_c^2 (\varepsilon _k ) = F_0^2 \left( {1 + \Lambda _{SPP}^2 + \Lambda _{SPP} \Lambda _{DDI}^{MNP} } \right)} \\ \end{matrix} , \hfill\cr \begin{matrix} {} & {F_0^2 = {{\varepsilon _k^2 \in _c } \over {h^2 c^2 }}} \\ \end{matrix} \hfill\cr}}$$$ …”

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

“…Taking into account the influence of the rate of nonradiative decay on a waveguide system is of fundamental importance when choosing its parameters. [45] Therefore, we optimize the system parameters in order to reduce the contribution of radiation and phonon losses and to obtain the maximum possible rate of SPP generation Γ SPP in two stages. At the first stage, using simple analytical calculations, [20] we select a suitable combination of QD radius and its distance to a single graphene sheet.…”

“…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. Using numerical simulation based on the finite difference time domain method, we reveal an unusual regime of a low-frequency modulation of the SPPs excited in the graphene waveguide by the SPPs excited on the gold stripes.…”