Resonantly Enhanced Emission from a Luminescent Nanostructured Waveguide.

Yasuhisa Inada,Takeyuki Yamaki,Shogo Tomita,Mitsuru Nitta,Taku Hirasawa,Akira Tsujimoto,Akira Hashiya,Masa-Aki Suzuki

doi:10.1038/srep34396

Abstract

Controlling the characteristics of photon emission represents a significant challenge for both fundamental science and device technologies. Research on microcavities, photonic crystals, and plasmonic nanocavities has focused on controlling spontaneous emission by way of designing a resonant structure around the emitter to modify the local density of photonic states. In this work, we demonstrate resonantly enhanced emission using luminescent nanostructured waveguide resonance (LUNAR). Our concept is based on coupling between emitters in the luminescent waveguide and a resonant waveguide mode that interacts with a periodic nanostructure and hence outcouples via diffraction. We show that the enhancement of resonance emission can be controlled by tuning the design parameters. We also demonstrate that the enhanced emission is attributable to the accelerated spontaneous emission rate that increases the probability of photon emission in the resonant mode, accompanied by enhanced the local density of photonic states. This study demonstrates that nanostructured luminescent materials can be designed to exhibit functional and enhanced emission. We anticipate that our concept will be used to improve the performance of a variety of photonic and optical applications ranging from bio/chemical sensors to lighting, displays and projectors.

Highlights

Techniques for controlling photon emissions have attracted much research attention due to their potential for application ranging from photonic devices to more commonly used optical devices[1]
D, the Aloss curve in the scattering experiment shows agreement with the calculation, whereas the Aemi from the PL experiment shows a significantly larger value than the Aloss. These results suggests that, as mentioned above, luminescent nanostructured waveguide resonance (LUNAR) emission (Aemi) can be attributed to the modified directional pattern of the emission in accordance with the local density of photonic states (LDOS) (Aloss), and to the increased spontaneous emission rate, which enhances the probability of photon emissions to the resonant mode
The enhancement of the directional and polarized emission can be attributed to the enhanced spontaneous emission rate, combined with the large LDOS of the resonant mode that is supported by the luminescent nanostructured material

Summary

Introduction

Techniques for controlling photon emissions have attracted much research attention due to their potential for application ranging from photonic devices to more commonly used optical devices[1]. Microcavities[2,3], photonic crystals[4,5] and plasmonic structures such as plasmonic nanocavities[6,7] and nanoantennas[8,9] have been explored to modify spontaneous emission by confining photons within a space smaller than their optical wavelength. These techniques enable high controllability of photon emission through a precise overlap between the emitter and the spatially-confined resonant mode, and have major potential for use in photonic devices such as low-threshold lasers and single-photon sources. We propose the use of nanostructured waveguide resonance (LUNAR) to enable the simultaneous control of a number of emitters with high efficiency

Methods

Results

Conclusion