Emission properties of quantum dots in polymer optical fibres

Optical and Structural Characteristics of CdSe/PMMA Nanocomposites

Nanocomposites of polymethylmethacrylate (PMMA) and CdSe were fabricated by a casting technique. The result showed that CdSe@PMMA can be used in white and green light emitting devices. 0.01CdSe@PMMA exhibits monochromatic green color emission with the highest fluorescent quantum yield and lowest optical band gap value, while CdSe@PMMA with other ratios shows a multicolor emission. The band-edge emits in the vicinity of 280 – 296 nm but a more stable intensive green color emission at 553 nm is found for 0.01CdSe@PMMA. The change in Eg (4.18 to 4.4) eV values is due to the interaction between the PMMA polymer and CdSe.

Microstructures in Polymer Fibres for Optical Fibres, THz Waveguides, and Fibre-Based Metamaterials

This paper reviews the topic of microstructured polymer fibres in the fields in which these have been utilised: microstructured optical fibres, terahertz waveguides, and fibre-drawn metamaterials. Microstructured polymer optical fibres were initially investigated in the context of photonic crystal fibre research, and several unique features arising from the combination of polymer and microstructure were identified. This lead to investigations in sensing, particularly strain sensing based on gratings, and short-distance data transmission. The same principles have been extended to waveguides at longer wavelengths, for terahertz frequencies, where microstructured polymer waveguides offer the possibility for low-loss flexible waveguides for this frequency region. Furthermore, the combination of microstructured polymer fibres and metals is being investigated in the fabrication of metamaterials, as a scalable method for their manufacture. This paper will review the materials and fabrication methods developed, past and current research in these three areas, and future directions of this fabrication platform.

Temperature effects on emission of quantum dots embedded in polymethylmethacrylate

We successfully used CdSe/ZnS quantum dots (QDs) as a dopant within a polymethylmethacrylate (PMMA) matrix. This doped material was used in the fabrication of a microstructured polymer optical fiber whose photoluminescence was characterized. A detailed analysis of the emission properties of the QDs as a function of temperature is presented, with the temperature dependence of this emission broken into components to show contributions from the thermo-optic effect of the PMMA and the temperature-dependence of the bandgap of the QDs.