title: Plasmonic chirality of L-shaped nanostructure composed of two slices with different thickness.
abstract: A concise method is proposed to fabricate L-shaped Ag nanostructures (LSANs) for generating chirality. Prepared by glancing angle deposition, the LSAN composed of two slices with different thickness is stacked on self-assembled monolayer polystyrene nanosphere arrays by controlling substrate azimuth and deposition time. The strong optical chirality of LSANs is achieved in visible and near-IR regions by measurement. For the circular dichroism spectrum of LSANs, the intensity is enlarged, and its peaks red-shift with increasing thickness difference. When LSANs are stacked on polystyrene spheres of different diameters, enlargement and red-shift are also observed in their circular dichroism spectra with increasing thickness difference. The numerical calculations of finite element method show that the two slices composing LSAN provide cross-electric dipoles and their thickness difference provides phase difference for generating optical chirality. This study not only provides a concise and scalable method for fabricating chiral plasmonic nanostructures but also contributes to understand the knowledge of the mechanism of circular dichroism.
authors.forename: Yongkai
authors.initials: Y
authors.lastname: Wang
authors.forename: Junchen
authors.initials: J
authors.lastname: Deng
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.forename: Tong
authors.initials: T
authors.lastname: Fu
authors.forename: Yu
authors.initials: Y
authors.lastname: Qu
authors.forename: Zhongyue
authors.initials: Z
authors.lastname: Zhang