Active Polarization Modulation of Terahertz Radiation Using Metamaterial/Graphene-Based Optoelectronic Devices

We investigate the modulation performance of a metamaterial/graphene optoelectronic device in the THz range. Operating characteristics such as amplitude, phase and polarization modulations of broadband THz radiation are reported. The accomplishments of modulation depth include >75% in spectral amplitude, >15 degrees in spectral phase, >0.2 active modulation of ellipticity ratio, and active rotational angle changes of 20 degrees. These achievements are the key elements towards efficient manipulations of THz radiation for applications such as next-generation wireless communications, spectroscopy, and imaging.