Optofluidic In-plane Mach-Zehnder Interferometer based on the liquid core/liquid cladding waveguides for Refractive-Index measurements

In this paper, we have employed the L-2 waveguides in order to guide the light into two different arms constructed by the inclusion of an engineered obstacle in front of the input optical port. The light which travels inside the core liquid is coupled into these two arms experiencing different optical paths due to the asymmetric geometry of the obstacle and also the different used cladding liquids. We have used several sets of coupled hydrodynamic-electromagnetic simulations to characterize the interferometer based on the output intensity of the waveguide. The simulation results indicate that this technique has a maximum sensitivity of 595%/RIU and a maximum resolution of 3.3x10(-6) RIU which depends on the range of flow rate.