Circular dichroism in planar nonchiral metamaterial made of elliptical nanoholes array

Pseudo-planar conjugated swastikas metamaterial with giant circular dichroism and negative refraction at near-infrared region

“…It can be observed that there exist two CD peaks at resonances. In addition, the maximal value (absolute value) of CD is up to 26 dB at lower frequency resonance of 140 THz, which is much comparable with the previous reported planar bi-layer chiral and single-layer non-chiral structures [8][9][10][11][12][13][14][26][27][28][29][30][31][32][33][34][35].…”

Giant Circular Dichroism and Negative Refractive Index of Chiral Metamaterial Based on Split-Ring Resonators

“…Although the CD phenomenon also can be observed in planar as well as double-layered non-chiral MMs structures [24][25][26][27][28][29], it is usually very small (|∆| < 0.4) and required an oblique incident wave. It is expected that 3D or 2D CMMs, like multilayered helical or doublelayer gammadion structures, are likely to exhibit CD effect and/or large optical activity.…”

Complementary Y-shaped chiral metamaterial with giant optical activity and circular dichroism simultaneously for terahertz waves

“…Optical activity, the ability to rotate the polarization plane of EM waves due to the lack internal mirror symmetry of CMM, which could be constructed as a cross-polarization convertor or 90°polarization rotator (11,12). The CD effect refers to the transmission intensity difference between the RCP and LCP waves, which could construct a pure circular polarizer or linear-to-circular polarization convertor (10,15,22,(33)(34)(35)(36)(37)(38)(39). Generally, optical activity and CD effect can be obtained by the fourfold rotationally (C 4 ) symmetric CMM design.…”