Figure 3: Theoretical calculations on chiral switching metamaterials.
From: Photoinduced handedness switching in terahertz chiral metamolecules
(a) Schematic of the chirality switching metamaterial. The unit cell consists of four chiral resonators with fourfold rotational symmetry. The key geometrical parameters are labelled in the figure. (b) The transmission spectra of left-handed (solid) and right-handed (dashed) circular polarizations, without (black) and with (red) photoexcitation. The shaded region represents the frequency range where the relative transmission amplitude between LH and RH polarization is reversed. (c) The ellipticity calculated from the transmission spectra without (black solid) and with photoexcitation (red solid). In the shaded area the sign of circular dichroism is flipped. (d) The optical rotatory dispersion (ORD) without (black solid) and with optical pumping (red solid). These numerical results show good agreement with the experimental observations.
