Multiband Fano Resonance in Symmetry Broken Planar Terahertz Metamaterial

This manuscript presents the experimental demonstration of multi-band Fano resonances in planar terahertz metamaterial. The proposed metamaterial structure resonates at two distinct frequencies at 0.25THz and 0.4275THz respectively. The broken in the structural symmetry provides two other Fano resonances at 0.27 and 0.31THz respectively in addition to the desired resonances. The variation in the two Fano resonances for broken geometrics is studied numerically using CST Microwave studio software and the geometrical parameters are optimized for the desired resonances. The transmission characteristics for various incident angles have been done to analyze the structure for angular independency operation. In addition, the current distributions through the surface of the metamaterial structure are also studied numerically. The optimized metamaterial geometry can be fabricated easily using femtosecond laser micromachining process.