Incident-angle-insensitive and polarization independent polarization rotator.

This paper proposes a method to design an incident-angle-insensitive polarization-independent polarization rotator. This polarization rotator is composed of layers of impedance-matched anisotropic metamaterial (IMAM) with each layer's optical axes gradually rotating an angle. Numerical simulation based on the generalized 4x4 transfer matrix method is applied, and the results reveal that the IMAM rotator is not only polarization-independent but also insensitive to the angle of incidence. A 90 degrees polarization rotation with tiny ellipticity variation is still available at a wide range of incident angles from 0 to 40 degrees, which is further confirmed with a microwave bi-split-ring resonator (bi-SRR) rotator. This may be valuable for the design of optoelectronic and microwave devices.