  The ability to control waves at the nanoscale has attracted considerable
attention to ultrathin metasurface lenses (metalenses) in optical imaging and
encryption systems. We propose an approach to active tuning metasurfaces by
integrating an ultrathin layer of indium-tin-oxide (ITO) into a unit cell as an
electro-optically tunable material. A proposed design features two orthogonal
wings that can independently manipulate waves with corresponding orthogonal
polarizations. The charge carrier concentration in the ITO accumulation layer
is altered by modulating the applied bias voltage. This bias voltage generates
phase variations at terahertz frequencies for the reflected transverse electric
and transverse magnetic polarized waves. It is possible to move both focal
points of a metalens without any physical movement by varying the bias voltage.
In addition, this paper explores the application of virtually moving metalens
for a novel multiple-input and multiple-output (MIMO) communication
architecture. We demonstrate a communication system based on single-point
binary data communication and hexadecimal orbital angular momentum (OAM) data
communication. Then, orthogonal channels can be used for MIMO communication
with high capacity. The proposed design paves the way for high-speed
communications as well as polarization-controlled molecular imaging systems.
