A Liquid Crystal Based Tunable Metamaterial Absorber with Wide Incident Angle Stability

A tunable metamaterial absorber was presented in this paper and the controllable dielectric constant of liquid crystals is utilized to realize a tunable absorption. The absorption spectra of the tunable absorber was calculated and analyzed. The proposed absorber achieved a frequency tunability of 6.19% by changing the dielectric constant of LC from 2.47 to 3.06. The results of numerical simulation also demonstrated that this absorber has polarization-independent behavior under normal incident waves. Moreover, the absorber shows a wide incident angle stability where the absorption frequency is insensitive to wave incident angle, and the absorption maintains high under both TE- and TM- polarized wave up to the 60° incident angle.