Fig. 1
a Patterned structure of periodic monolayer graphene. b Single-layer graphene patterned unit structure. c The cross-sectional view of the structure and circuit diagram. d Preparation diagram of the provided structure metamaterial. Here, the geometric parameters of the structure are as follows: a = b = 1.5 μm, c = d = 0.2 μm, e = 0.3 μm, f = 1.4 μm, i = 4 μm; g = 1.6 μm, h = 0.5 μm