Tunable Plasmonic Absorber Based on TiN-Nanosphere Liquid Crystal Hybrid in Visible and Near-Infrared Regions

In this paper, a tunable plasmonic absorber based on TiN-nanosphere/liquid crystal (LC) nanocomposite in visible and near-infrared regions is proposed. TiN-nanosphere/LC nanocomposite is a combination of titanium nitride (TiN) nanospheres dispersed in a host of LC and plays the main role in post fabrication tunability. The proposed absorber has three more than 90% absorption peaks and the absorption tunability of about 76 nm. It is shown that TiN-nanospheres are able to support localized surface plasmon resonance (LSPR). The Maxwell-Garnett theory is utilized to approximate the permittivity of the composite structure. Also, the effect of geometric parameters on the absorption is studied. Moreover, a single sheet of graphene is utilized to compensate the decrement of the absorption caused by the geometric parameters.