Tunable intrinsic chirality obtained by combining the extrinsic chiral structure on an anisotropic substrate

In this work, we designed a composite intrinsic chiral structure through introducing an anisotropic environment around the extrinsic chiral structure. The designed structure is made up of an extrinsic chiral nanocrescent based on an anisotropic substrate. The simulation results of the extinction show that intrinsic chirality can be obtained and tuned by changing the angle between the optical axis of the anisotropic substrate and the mirror axis of the nanocrescent (f). The maximum value of circular dichroism (CD) is up to about 0.035. Additionally, according to the charge distributions, the obtainment of our intrinsic chirality is originated from a new symmetry breaking introduced by the anisotropic substrate to the extrinsic chiral structure. This study could provide a new perspective for understanding chirality generation and could promote the application of chirality in imaging, sensing, etc.