Optofluidic sensor engineering towards plutonium concentration measurements

摘要

Research in nuclear safety and fuel reprocessing has led to a surging need for novel chemical analysis tools with reduced analyte and effluent volumes. Recent technological advances for the elaboration and packaging of glas s optofluidic cointegrated sensors have opened up the way for said analysis in harsh environments. We discuss a sensor engineering approach for the construction of an integrated absorption spectrometer with an ion-exchange core. Pu(VT) oxidation state exhibits a major absorption peak at a wavelength of 831 nmwith a molar absorption coefficient of 545 LmoL~(-1)'.cm~(-1). An evanescent waveguiding sensing structure that allows guided fluid/light interaction is investigated in orderto provide absorption spectroscopy measurements. The work presented consists of optical simulations as well as experimental measurements. Waveguide engineering with respects to modal transmission, field/fluid interaction coefficient T and device losses is presented. The simulations are carried out by computing ion-exchanged waveguide refractive index distribution and using it in mode solver software. Device optical characterization and bench tests are carried out to verify approach viability. First device measurements of a neodymium absorption peak in nuclear manipulation conditions are displayed.