Fabrication of Chiral Materials in Nano- and Microscale

Abstract

Artificial chiral materials at the nano- and microscales have unique optical properties, known as optical activities, that correspond to preferential interactions with circularly polarized light. Unlike the chiroptical responses of biomaterials, nano- and microscale materials with artificial chirality can present intense and tunable chiroptical responses in a broad range of frequencies from the ultraviolet to terahertz regimes. These particular properties of artificial chiral materials have been highlighted because of their potential use in photoelectronic and biomedical applications. The precise fabrication and manipulation of such small-scale materials are among the most important factors affecting their applicability; however, improvements remain necessary. From this perspective, we provide an overview of this field with introductions to types of artificial chiral materials, major parameters in the determination of chiroptical properties, fabrication methods that focus on mechanical-instability-induced buckling methods, and inclined-angle deposition methods. We also present application areas and outlooks.

Chiral Plasmonic Nanowaves by Tilted Assembly of Unidirectionally Aligned Block Copolymers with Buckling-Induced Microwrinkles

“…Recent advances in the field of chiral nanomaterials have drawn great attention because of the distinctive chiroptical properties of such nanomaterials , and their potential applications in advanced optical and biomedical devices, such as metamaterials, , holographic displays, chiroptical field separations, , and biosensor platforms. , Nanostructured materials with chiral geometries can preferentially interact with circularly polarized light in specific wavelength ranges that are mainly attributed to the electronic transitions, charge transfer, and plasmonic absorptions of the constituent materials. The three-dimensional shapes of chiral structures significantly affect the appearance and magnitude of chiroptical responses.…”

Chiral plasmonic nanostructures: recent advances in their synthesis and applications

“…Many bottom-up techniques using vacuum-based deposition of a metal precursor or metal vapor have been employed to fabricate chiral nanostructures of various shapes, including helices. 67 Thus, focused ion beam and electron beam induced deposition (FIBID/FEBID) are two classical examples of bottom-up methods. [68][69][70] They consist of depositing materials contained in a vaporized precursor molecule which is decomposed by an ion/electron beam (Fig.…”

Nanoengineering with RAFT polymers: from nanocomposite design to applications

“…Plasmonic nanoassemblies with chirality have been of special interest for their exceptionally strong chiroptical properties. 355,356 These properties have very high potential in bioanalytical applications, for example, biosensing 356,357 and medical diagnosis. 356 The preparation of these chiral nanostructures was dominated by biomolecular linkers like amino acids, 358 peptides, 359 and DNA 356,[360][361][362] due to their inherent chirality.…”