Integrated nanoantennas and metasurfaces have been very hot topics in the last two decades, and they play very important roles in telecommunications, integrated sensing devices, optical interconnectors just to name a few. Traditionally, integrated photonic crystals, Mach Zehnder waveguides interferometers, ring resonators, gratings are the key elements for integrated photonic circuits, however, they are bulky and there is a room to decrease further the functional areas to make more compact integrated photonic chips. Due to their ability to confine light to sub-wavelength volumes plasmonic nanoantennas can serve as a fundamental link between electronic and photonic circuits as they can bridge large size mismatch between the electronic and optical wave function. Thus, plasmonic elements can be utilized to increase the integration density and performance of active and passive photonic devices as well as to include new functionalities and concepts for photonic chips. Therefore, our goal is to design subwavelength functional areas by utilizing plasmonic meta-atoms to manipulate both far-field and localized light and integrate these plasmonic functional areas into dielectric optical waveguides. However, plasmonic materials suffer from their intrinsic absorption. All-dielectric nanoantennas, on the other hand, exhibit high radiation efficiencies, but the lower field confinement and enhancement also reduce coupling efficiencies. Therefore, we applied different materials for different applications based on maximizing the devices’ performances. In this seminar, I will present my work on the integration of plasmonic elements with silicon waveguides, such as the band spectrum splitting by using a single Fano nanoantenna, and polarization demultiplexing by utilizing a dragon fly shape gold antenna. Furthermore, I will also show our works on hybrid and all dielectric metasurfaces in localized light manipulating, biosensing, and opto-mechanics applications.