  We conceptualized three-array scalable metasurfaces comprising only three
thin strip grids and numerically demonstrated their characteristics in the
mid-infrared spectral regime for switchable polarization manipulation and
related asymmetric diodelike transmission (AT). A few or all of the grids were
taken to be made of VO$_2$, a phase-change material. For each proposed
metasurface, two effective structures and, therefore, two different
functionalities exist, corresponding to the metallic and insulating phases of
VO$_2$. The achieved scenarios of functionality switching that depend on the
VO$_2$ phase are shown to significantly depend in the way in which VO$_2$ is
incorporated to the metasurface. Switchable bands of polarization manipulation
are up to 40 THz wide. The AT band can be modulated when Fabry--Perot
(anti-)resonances come into play.

Optics;Applied Physics