Graphene Plasmonic Crystal: Two-Dimensional Gate-Controlled Chemical Potential for Creation of Photonic Bandgap

AbstractA new design of graphene-based plasmonic waveguide is presented and its transmission properties are studied. The transmission channel is such designed that the chemical potential of graphene is periodically changed in two dimensions by application of voltage bias through a patterned substrate. Because of periodicity of structure, it shows a forbidden bandgap at terahertz (THz) frequencies similar to a conventional photonic crystal. The effect of different structure parameters on the rejection band frequency range is numerically studied and the switching function of the proposed waveguide is observed with rejection efficiency of more than 99%. The reported relation between center frequency of the rejection band and also FWHM with the related chemical potential of the 2D-GPC confirm the real-time tunability of the proposed structure employing an external bias voltage. According to the ultra-integrated size of the structure and its remarkable optical efficiency in THz range, such a realization can pave the way for further development in band rejection –based nanoplasmonic applications such as filtering and switching devices.
Source: Plasmonics - Category: Biomedical Science Source Type: research