Single-Photon Emission by the Plasmon-Induced Transparency Effect in Coupled Plasmonic Resonators

Wei Wei,Xia Zhang,Xin Yan,Qi Liu

doi:10.3390/photonics8060188

Abstract

The plasmon-induced transparency (PIT) effect with unique spectrum transmission characteristics is a significant property of plasmonic structures. A resonant nanocavity with nanoscale dimensions around a single-photon emitter dramatically enhances the emission rate of the emitter. Thus, we propose detuned resonant nanocavities to manipulate the emission rate of the emitter inside, of which either cell consists of a rectangular resonator surrounded by a U-like resonator. An InGaAs quantum dot in a GaAs nanowire placed in the center of the detuned resonant nanocavity was employed as a single-photon emitter. The finite-difference time domain simulation revealed that the distribution of the electromagnetic field can be affected by changing the coupling intensity between the bright and dark states of the PIT. Consequently, the emission rate of the single-photon emitter was dramatically enhanced by more than 2000 times due to the Purcell effect induced by the PIT in the resonant cavity. With the achievement of an ultrafast single-photon emission rate, the proposed single-photon emitter could have diverse applications in quantum information and quantum communications.

Highlights

Due to the quantum interference between different excitation pathways in a multilevel atomic system, an optically opaque medium can be rendered transparent for coherent laser radiation, and a narrow spectral range appears in an absorption line, which is known as the electromagnetically induced transparency (EIT) [1]
The dark resonator is strongly excited, while its counterpart is suppressed. This is similar to the EIT effect of an atomic system, where cancellation of the Photonics 2021, 8, 188
As the spontaneous emissivity of the emitter is proportional to the local density of the optical state, for an emitter placed in a homogeneous medium, its spontaneous emission rate is not constant depending on the transition dipole moment of the emitter and the dielectric constant of the surrounding medium

Summary

Introduction

Due to the quantum interference between different excitation pathways in a multilevel atomic system, an optically opaque medium can be rendered transparent for coherent laser radiation, and a narrow spectral range appears in an absorption line, which is known as the electromagnetically induced transparency (EIT) [1]. A number of configurations have been proposed to realize the EIT-like transmission under mild experimental conditions, such as coupled dielectric resonators [3,4], metamaterial-induced transparency [5,6], phase-coupled plasmon-induced transparency [7] and some other multi-layer structures [8,9,10,11]. Among them, plasmoninduced transparency (PIT) based on surface plasmon polaritons (SPPs) attracted significant attention due to its slight restrictions on the experimental realization [12,13,14,15,16]. Metal–insulator–metal (MIM) structures are Photonics 2021, 8, x of significance due to supporting lightwave propagation in the deep sub-wavelength scale. The enhancement is realized by the on-chip MIM-based PIT in integrated plasmonic components using detuned coupling resonators that are aperture side-coupled to a bus waveguide. QD were of investigated ation of the QDNW inside the bus waveguide, air gaps exist between the NW surface and

Structure

Results and Discussion

Purcell

4.4.Conclusions