The goal of this project is to demonstrate by simulations the relevance of fabricating nanowired structures for integrated optical applications. Indeed, subwavelength nanostructures present the advantage of guiding consistently the light, while having also large evanescent fields. Therefore, they are very sensitive to small variations in their surrounding environment. In this report, the powerful of these particular microsystems have been proved by implementing them in a highly sensitive Mach-Zehnder Interferometer (MZI) configuration. In fact, in the device studied and illustrated in Figure A, only the sensing area is made of multiple nanowires. This gives the opportunity to change the light behaviour only in the sensing arm and thus to phaseshift its light beam with respect to the reference one. Additionally to this main concept, two other principles are crucial to design this sensor. Indeed, without adding Anti-Resonant Reflective Optical Waveguides (ARROWs) structures, it would have been impossible to confine the light in the top polymeric layer, since its refractive index is lower than the one of the silicon substrate. Furthermore, the Multi-Mode Interference (MMI) couplers are useful configurations to split and combine light beams, since they are very simple to design and fabricate. Technologically, these structures are fabricated in an hybrid polymer (the Ormocomp) in order to simplify the manufacturing. Indeed, a cost- and time-efficient Nano-Imprint Lithography Process (NIL Process) can be implemented, leading furthermore to precise final structures.