MILOO: Directed and enhanced photoluminescence of quantum dots using all-dielectric nanoantennas
Research project selected under the 2016 call for proposals
Principal Investigator :
Aurélien CUCHE ()
CEMES (NeO)
Type of project : Collaborative Project
Partner team(s) :
LPCNO (Nanotech et Quantum optoelectronics )
Date (start/end) : 2017 - 2019
Sketch of a complex optimized Si nanoantenna on silica, able to scatter efficiently two separate wavelengths in different regions of space as function of the excitation light polarization, with different QDs positioned at the center by nanoxerography. Absorption and emission bands of the QDs will be tuned to fit the antenna characteristics (or inversely).
Abstract
The field of nano-optics is nowadays mainly driven by plasmonics since noble metal nanoantennas support surface plasmon resonances that can be used to manipulate, concentrate or redirect visible light. These appealing properties have led to numerous current or potential applications in integrated optics, sensors or field-enhanced spectroscopies. Recently, high-refractive index dielectric resonators, typically silicon nanostructures, have attracted increasing interest since they offer similar possibilities, but with specific advantages like a reduced dissipation.
High-refractive index dielectric nanoantennas possess optical resonances of “electric” or “magnetic” nature in the visible spectrum. The interplay between such resonant modes allows manipulating macroscopic properties like light scattering directionality. The resonances also induce a strong enhancement of the electric near field, which can be used to control the emission of emitters placed the in the vicinity of the antennas. In this project, AFM nanoxerography will be used for spatially controlled deposition of emitters (quantum dots) above dielectric antennas, which are realized by a top-down approach in Silicon on Insulator. Spatially and time resolved information about the near-field hot spots and the photodynamics will be obtained by mapping the photoluminescence of the quantum dots. The polarization-dependent enhancement and directionality of the antenna will be optimized at different wavelengths by the mean of an Evolutionary Optimization Algorithms. The project thus aims at designing a photonic device composed of all-dielectric antennas, allowing to both improve the emission of different quantum emitters and to simultaneously focus the whole emission in a preferred direction for each wavelength.