RT info:eu-repo/semantics/bachelorThesis
T1 Aplicaciones de microesferas transparentes en sensores de temperatura y presión
A1 Estévez Alonso, Pablo
K1 Microesferas
K1 neodimio
K1 WGM
K1 FIR
K1 sensibilidad relativa e incertidumbre
AB The results of this study are focused on analyzing the changes of certainphenomena that occur in a transparent microsphere of oxyfluoride glass dopedwith neodymium with the temperature and pressure to find out if it is possible todevelop sensors of both magnitudes.In recent years, several studies have been carried out on different new materialsto exploit their particular properties. Such is the case of materials doped with rareearths, whose optical and magnetic properties make them very useful in fields suchas medicine or condensed matter physics. But for the case at hand, the interest ofthis study lies in the viability of transparent neodymium-ion-doped oxyfluorideglass microspheres for the creation of optical temperature and pressure sensors.For such purpose, two phenomena were studied: the displacement of theWhisppering Gallery Modes (WGM) peaks and the variation of the intensities ofthermally coupled levels through the relationship between fluorescence intensities(FIR):-WGM is a phenomenon of resonance of electromagnetic radiation within a cavityby multiple internal reflections within the cavity, in this case, the microsphere. Asthis phenomenon depends on the geometry and the difference of refractive indexbetween the material and the environment, a change in the refractive index and/orthe size of the microsphere modifies the wavelengths of the WGM resonances, afact that can be used to study how a change in the environment affects the material.-On the other hand, the FIR technique consists in calculate the temperature ofa material by using the thermal coupling between two populations of two excitedlevels that can be very close energetically. This last case is interesting because theratio for the intensity of both populations would depend exclusively on thetemperature of the system that has those two levels through Boltzmann’s function.This technique only needs the emission of two energy levels, then it is independentof the geometry used to observe them.The uncertainty of these parameters and the relative sensitivity are used toevaluate the quality of the microspheres as temperature and pressure sensors.
YR 2020
FD 2020
LK http://riull.ull.es/xmlui/handle/915/21545
UL http://riull.ull.es/xmlui/handle/915/21545
LA es
DS Repositorio institucional de la Universidad de La Laguna
RD 22-nov-2024