Vol. 45, Issue 3, pp. 327-340 (2015)

Abstract

In this study, we investigate the sensing applications in the presence of the nonlinear effects by proposing an all-optical sensor and considering nonlinear effects on modal propagation and output intensity based on an ultra-compact nonlinear multimode interference coupler. The sensor can be tuned to have the highest sensitivity in the wavelength and refractive index ranges and can detect water-soluble chemicals, air-pollutions, earthquake wave, blood parameters, and heart operation. The results indicate high output sensitivity to input wavelength whereas the nonlinear effects appear in the medium. This sensitivity led us to propose a wave sensor of both transverse and longitudinal waves, such as acoustic and light waves, when an external wave interacts with an input waveguide. For instance, this sensor can be implemented using a long input that is inserted in the land, and any wave could then be detected from the Earth. The visible changes in intensity at the output facet in various refractive indices of the surrounding layer show the high sensitivity to the refractive index of the surrounding layer, which is the foundation of introducing a sensor. Generally, the results show the high efficiency of nonlinear effects in all-optical sensing performances.