Circular Dichroism Induced by the Coupling between Surface Plasmon Polaritons and Localized Surface Plasmon Resonances in a Double-Layer Complementary Nanostructure

Abstract

Circular dichroism (CD) spectroscopy is an important technique for detecting and identifying chiral molecules in the fields of chemistry, biology, and other life sciences. Artificial plasmonic nanostructures exhibit considerable CD effects, but the preparation of 3D and multilayer chiral structures that exhibit large CD signals is usually difficult. Strong CD effects and simple fabrication processes are necessary. In this study, double-layer complementary nanostructures (DLCNs) that can generate prominent CD signals are prepared with a simple experimental method. Numerical calculations show that the physical mechanism underlying the CD effect is the coupling between localized surface plasmon resonances excited in complementary nanostructures and surface plasmon polaritons excited on a metal nanofilm under left-circularly polarized and right-circularly polarized light illuminations. The CD effect can be tuned by changing the parameter of the DLCN array. Results provide a way to generate CD effects with spatially complementary nanostructures and may provide an avenue for the chiral manipulation of light. These chiral nanostructures can be fabricated through simple methods, have considerable CD signals, and provide insights into the chiral optical response, providing novel tools for the design of chiral optoelectronic devices.

Chiral Lattice Resonances in 2.5-Dimensional Periodic Arrays with Achiral Unit Cells

“…The prospects of these applications have triggered the study and characterization of a variety of periodic arrays supporting chiral lattice resonances. − The majority of these arrays are built from the repetition of chiral unit cells, made of either individual nanostructures with complex chiral morphologies, − , such as helices, or multiple nanostructures forming a chiral arrangement. , As expected, the lattice resonances supported by these systems exhibit different responses under illumination with right- and left-handed circularly polarized light. More recently, it has been shown that the combination of a rectangular lattice with an achiral unit cell results in arrays capable of supporting lattice resonances with some degree of chirality, which can be enhanced by positioning the array in an inhomogeneous dielectric environment .…”

“…56−64 The majority of these arrays are built from the repetition of chiral unit cells, made of either individual nanostructures with complex chiral morphologies, [56][57][58]63 such as helices, 60 or multiple nanostructures forming a chiral arrangement. 65,66 circularly polarized light. More recently, it has been shown that the combination of a rectangular lattice with an achiral unit cell results in arrays capable of supporting lattice resonances with some degree of chirality, which can be enhanced by positioning the array in an inhomogeneous dielectric environment.…”

Enhancement and sensing applications of ultra-narrow band circular dichroism of the chiral nanopore films based on Bragg reflector

“…Areas other than the chiral L hole were then scanned using electron beam exposure. 20 The subsequent development, fixation, and drying subsequently yield chiral nanorods of the same size as the chiral L-shaped hole. Later, SiO 2 and Si layers were deposited alternately on the substrate and applied to the samples.…”

Active Control and Sensing Application of Ultra-Narrowband Circular Dichroism in Multilayer Chiral Nanorod Arrays

“…The following steps can be taken to achieve the structure mentioned above: First, the complementary chiral nanopore array to the chiral nanorod array is prepared on the gold substrate by electron beam lithography technology. 35 Then, SiO 2 and lithium niobate thin films are alternately deposited on their surface by physical vapor deposition technology. 36 Finally, the excess photoresist around the structure is removed by the peeling method to form MCNAs.…”