Metamaterial anti-reflection lining for enhancing transmission of high-permittivity plate

In this letter, we propose the design of anti-reflection (AR) lining for enhancing transmission of high-permittivity dielectric (HPD) plate based on locally modified Fresnel law. By applying metamaterial unit cells on the air-dielectric interfaces, the fields are distorted locally in the HPD, leading to split and tilted wave-vectors in sub-wavelength scale. Due to the tilted wave-vectors, the reflection and refraction on the interface are locally modified without violating Snell’s law, leading to reduced reflection and hence enhanced transmission according to Fresnel equations. As an example, we demonstrate two prototypes that enhance the transmission of a 3 mm thick alumina plate below and above the half-wavelength frequency. Both the simulation and measured results verify the good transmission enhancement performance in X and Ku bands. This work provides an effective alternative to the design of AR structures for especially HPD materials.