Investigations and Analyses of Mach Zehnder Interferometery Based Fiber Optics Biosensors

Abstract

This thesis investigates an OMZI platform using optical waveguides. The emphasis of newlinethe thesis is on both theoretical and experimental aspects of Interferometer based biosensors newlineplatform. This platform can be readily used in practical engineering tasks of analysis of newlinebiomedical parameters. Accurate measurement of concentrations of solids, gases and liquid newlinehave become more and more important in chemical analysis, biomedical, food, environmental newlinemonitoring and in the semiconductor manufacturing area. The present study was based on newlineOptical Mach Zehnder Interferometer (OMZI) platform for Refractive Index (RI) newlinemeasurement application and deals with interferometer using single mode transmission. newlinePlanar, rib and strip waveguides based OMZI are analysed. Interferometer is very sensitive newlinemethod and it eliminates the need of tagging. OMZI are commonly used for these kinds of newlinebio-analysis. It is the real time monitoring processes. Waveguides under consideration are newlinevery small in size and faces difficulty in the light guiding into it. Instead of the penetration newlinedepth of evanescence wave, light guiding efficiency dominates the detection sensitivity of newlinestructure. So careful light guiding is an important aspect of the photonics waveguide newlinestructure. newlineThe main part is devoted to processing of an OMZI waveguide platform. OMZI is a newlinecommon interferometry technique that suits biosensing applications due to its robustness and newlinerigid sensing mechanism. As the concentration and hence the refractive index changes the newlinepath length of the light in measurement arm of the structure and this change in path length newlineproduces the corresponding changes in phase shift of light passing through it. Other arm is newlinereference arm in which phase shift remains constant. Tests have been carried out using Beam newlinePropagation Method (BPM) technique using Beam PROP software to analyze OMZI newlinestructure and measurement of refractive index of medium using this structure. We examine newlinethe behaviour of OMZI using Linear Y branches angle, evanescent field coupling and S-bend newlineY