Sökning: "upconversion."
Visar resultat 1 - 5 av 37 avhandlingar innehållade ordet upconversion..
1. Advancing Upconversion Emissions for Biomedical Imaging
Sammanfattning : During the past decade, upconverting nanoparticles (UCNPs) doped with rare earth ions have become an important class of fluorescence contrast agents for molecular imaging, due to their unique properties. Their property of anti-Stokes luminescence, with both the excitation and emission wavelengths close to the optimal for biomedical imaging, has been extensively explored in various biomedical applications. LÄS MER
2. Upconversion Detection for Improved Nonlinear Mid-infrared Spectroscopy in Flames
Sammanfattning : This thesis deals with the addition of upconversion detection to non-linear mid-infrared laser spectroscopy techniques. The techniques investigated here are degenerate four wave mixing (DFWM) and infrared polarization spectroscopy (IRPS). LÄS MER
3. Photon Upconversion in Heavily Doped Semiconductors
Sammanfattning : In this thesis the luminescence properties of highly doped semiconductors are studied with focus on degenerately n-doped InP. It is demonstrated how photoluminescence measurements on degenerately doped semiconductors allow an estimation of the doping concentration without need for electrical contacts. LÄS MER
4. Upconversion in Er doped silica : - characterization and modeling
Sammanfattning : Further increase of erbium concentrations in Er-doped amplifiers and lasers is needed for the design of efficient, reliable, compact and cost-effective components for telecommunications and other photonic applications. However, this is hindered by Er concentration dependent loss mechanism known as upconversion. LÄS MER
5. Intramolecular Electronic Interactions in Photon Upconversion and Singlet Fission
Sammanfattning : The sun provides our planet with an abundance of energy in the form of solar light – a continuous stream of photons. Increasing our direct utilization of solar energy will constitute a necessary part in our ongoing replacement of fossil fuels with energy sources free from greenhouse gas emissions. LÄS MER