Tunable left-handed metamaterial based on electrorheological fluids

A tunable left-handed metamaterial consisting of a periodic array of the left-handed dendritic structure units infiltrated with electrorheological fluids is demonstrated. Experimental results show that the passband can move from the original 8.50–10.60 GHz to 7.16–8.39 GHz after electrorheological fluids are infused. When a dc (direct current) electric field of 666 V/mm is applied, the passband moves toward lower frequency of within 7.08–8.30 GHz. This method provides one convenient way to design adaptive metamaterials.