Objective
The aims of this project are two-fold: (i) to control the structural properties of high porosity fcc matrices, e.g. artificial opal functionalising them by infilling the matrices with Ge, InP and GaP thus modifying their optical properties in the visible and near-infrared range; (ii) to examine and model the optical response of these composites under optical pumping to study PBG effects leading to the possibility of creating electroluminescent structures via the specific introduction of doped semiconductors.
We propose to use two methods to control the incorporation of semiconductors: sol-gel techniques and metal-organo chemical vapour deposition (MOCVD). An integral part of this project is the accompanying characterisation and modelling work. These are focused primarily on structural and optical characterisation and, to a lesser degree, on electrical characterisation.
If we gain control on the material to be introduced in the opal matrix, we would be in a position to produce PBG based light emitters of high efficiency with emission verging on laser action. The control of the opal composite structure and its refractive index determines the spectral region where the guest material will operate. Our target is to use these materials for controlled light emission in the first instance.
The study of nanocomposite formation can be seen as an essential step in the understanding of future nanocomposites with organic, magnetic and, in the not so distant future, biological infills. A suitable type of infill, would determine the functionality of these 3 dimensional structures be, for example, optical, electronic, magnetic or bioelectronic.
The improvement of light emitting devices is a continuing task of fundamental and applied research in the quest for progress in the field of photonics. Recently, two concepts are en vogue to address issues such as control of the spontaneous efficiency and the spatial control of light in 3 dimensions. These are the concept of photonic bandgap (PBG) and optical microcavities. One of the toughest races at present is the realisation of three-dimensional photonic crystals working in the visible range. In this context, the use of a three-dimensional grating combined with light emitting structures is a most promising way to suppress the spontaneous emission in the vicinity of the wanted emission mode. One such approach is the use of packages prepared by colloidal chemistry to test mirrorless lasing action, selective filter action, enhancement of dye luminescence due to distributed Bragg reflection and optical switching in the nanosecond scale. These materials can be described as PBG media if they have a high refractive index contrast between the medium and the light scattering centres. However, the inherent disadvantage of colloids is that any small perturbation causes them to melt, and of colloidal crystals that their diffractive efficiency is only 2% due to a high density of lattice defects. In this project we address the issue of solid three-dimensional (3D) gratings, which in principle have fewer defects and lend themselves to be modified further by the use of external electric fields. Furthermore, in their solid form they are more likely to be integratable in an optical system compared to a fluid material.
Fields of science (EuroSciVoc)
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques.
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques.
- engineering and technologymaterials engineeringcomposites
- natural sciencesphysical sciencescondensed matter physicssoft matter physics
- natural sciencesphysical scienceselectromagnetism and electronicssemiconductivity
- engineering and technologymaterials engineeringnanocomposites
- natural sciencesphysical sciencesopticslaser physics
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Topic(s)
Call for proposal
Data not availableFunding Scheme
ACM - Preparatory, accompanying and support measuresCoordinator
42119 Wuppertal
Germany