A General Mechanism for Achieving Circular Dichroism in a Chiral Plasmonic System

Abstract

AbstractChiral plasmonic (CP) systems are shown to exhibit effectual circular dichroism (CD). A general mechanism based on the Jones matrix for predicting the CD signal of CP systems is proposed. Considering the near‐field coupling of adjacent layers of trilayer CP systems, the coupling matrix, which shows the relevance of the coupling status to the relative position of the adjacent layers, is analytically derived under the framework of the transfer matrix method. To prove the coupling matrix, a trilayer system is designed, and the optical properties of the relevant system arrays are simulated using the finite‐element method. The fitting functions of the simulated CD signals at resonant wavelengths are consistent with the theoretical formulas. The proposed mechanism facilitates an understanding of the underlying physical mechanism of CD and offers a design principle for fabrication of CP systems that are applicable to biosensing.