Enhanced induced circular dichroism by asymmetric surface plasmon resonance mode

Chirality is a pervasive phenomenon in nature. The examination of chirality in biomolecules provides a means to detect their intricate structures. Certain pharmaceutical molecules necessitate precise chirality detection, given that variations in chirality can lead to disparate therapeutic outcomes. Unfortunately, the circular dichroism signal used to discern chirality is notably feeble. Consequently, the implementation of surface-enhancement techniques becomes imperative to amplify this signal and facilitate accurate chirality detection. Induced circular dichroism is a phenomenon generated by the near-field interaction between chiral molecules and nano-structures. Induced circular dichroism enhances detection sensitivity of molecular chirality, and to enhance induced circular dichroism, a detailed investigation of underlying mechanism of circular dichroism inducement is needed. In this paper, to enhance induced circular dichroism, we present numerical investigation on circular dichroism inducement mechanism. The induced circular dichroism was observed to be enhanced by asymmetric electric and magnetic dipole resonance modes. In contrast, for symmetric electric and magnetic dipole modes, the induced circular dichroism is minimal.