“…CMMs are of great current interest both for customized functionalities and for potential applications not found in natural medium arise from the magneto-electric cross coupling of chiral structures due to their lack of any mirror symmetry. As a fact, besides negative refractive index, CMMs can also achieve other exotic EM characteristics, such as giant gyrotropy [4], strong polarization rotation (giant optical activity) [5][6][7][8][9][10][11], circular polarizer (circular dichroism, CD effect) [12][13][14][15], asymmetric transmission (AT) effect [16][17][18][19][20][21], linear or/to circular polarization conversion [22][23][24][25][26][27][28][29][30][31][32], and even the prospect of a repulsive Casimir force [33,34] by special enantiomeric forms or similar chiral structure design. The cross-coupling is original physics of these special electromagnetic (EM) properties [35,36].…”