Surface Plasmon-Coupled Enhanced Transmission

TL;DR

This paper investigates surface plasmon-coupled enhanced transmission involving quantum emitters near metallic nanostructures, demonstrating energy transfer, radiative decay enhancement, and proposing a miniaturized transmission device with optimized surface gratings.

Contribution

It introduces a novel device design leveraging plasmonic resonance for efficient light transmission without epi-illumination, with detailed analysis of emitter-structure interactions and performance optimization.

Findings

Energy transfer occurs at sub-10 nm distances from metallic surfaces.

Resonant aperture enhances the emitter’s radiative decay rate.

Device performance depends on emitter position and orientation.

Abstract

For distances less 10 nm, a total energy transfer occurs from a quantum emitter to a nearby metallic surface, producing evanescent surface waves that are plasmonic in nature. When investigating a metallic nanohole supported on an optically dense substrate (such as diamond with nitrogen vacancy center), the scattering occurred preferentially from the diamond substrate towards the air for dipole distances less 10 nm from the aperture. In addition, an enhancement to the dipole's radiative decay rate was observed when resonance of the aperture matched the emitters wavelength. The relationship between an emitter and a nearby resonant aperture is shown to be that of the resonance energy transfer where the emitter acts as a donor and the hole as an acceptor. In conjunction with the preferential scattering behavior, this has led to the proposed device that operates in transmission mode, eliminating the need for epi-illumination techniques and optically denser than air superstrates in the collection cycle, hence making the design simpler and more suitable for miniaturization. A design criterion for the surface grating is also proposed to improve the performance, where the period of the grating differs significantly from the wavelength of the surface plasmon polaritons. Response of the proposed device is further studied with respect to changes in nitrogen vacancy's position and its dipolar orientation to identify the crystallographic planes of diamond over which the performance of the device is maximized.