  In view of the fact that most invisibility devices focus on linear
polarization cloaking and that the characteristics of mid infrared cloaking are
rarely studied, we propose a cross circularly polarized invisibility carpet
cloaking device in the mid infrared band. Based on the Pancharatnam Berry phase
principle, the unit cells with the cross circular polarization gradient phase
were carefully designed and constructed into a metasurface. In order to achieve
tunable cross circular polarization carpet cloaks, a phase change material is
introduced into the design of the unit structure. When the phase change
material is in amorphous and crystalline states, the proposed metasurface unit
cells can achieve high efficiency cross polarization conversion and reflection
intensity can be tuned. According to the phase compensation principle of carpet
cloaking, we construct a metasurface cloaking device with a phase gradient
using the designed unit structure. From the near and far field distributions,
the cross circular polarization cloaking property is confirmed in the broadband
wavelength range. The proposed cloaking device can effectively resist detection
of cross-circular polarization.

Optics