  In this paper, a wideband and low-scattering metasurface in terahertz (THz)
is introduced. The proposed coding metasurface is composed of four different
graphene square patches in one layer, which has a distinct bias voltage. By
optimizing the chemical potential of each patch, the reflection phase and
amplitude of a designed element can be controlled in a real-time manner. The
chemical potential optimizing approach is a promising method to develop
metasurfaces, which can tune the reflection phase, magnitude, or polarization
dynamically at different frequencies spectrum. Indeed, by adjusting the
metasurface reflection profile, the suggested device can manipulate the
reflected wave. Also, this metasurface can reduce reflection energy in the
wide-band spectrum. The programmable surface disperses reflected power in
various directions in a first frequency band and converts incident
electromagnetic waves into heat at second frequency band. The obtained results
demonstrate that more than 10 dB reflection reduction can be realized over 1.02
to 2.82 THz under both TE and TM polarized wave incidences. Due to the
conformal properties of the graphene monolayer, the stealth feature of the
metasurface is well preserved while wrapping around a metallic curved object.
This optimization method has an excellent aptitude for phase, magnitude, and
polarization control in various beamforming applications at the THz spectrum
for high-resolution imaging and stealth technology.
