New functionalities in new 2D materials: chemically exfoliated 2D crystals
Abstract
Approved for Public ReleaseExciting, physical properties, including frustrated magnetism, proximity to spin liquid behavior, or topological states of matter have been realized in bulk three-dimensional (3D) crystals. Though there are only few examples of two-dimensional (2D) crystals, fascinating quantum phenomena have already been reported in these thin materials that consist of only a single atomic layer; such phenomena include magnetism, correlations, and topology. 2D materials may be tuned in that they are gateable,and can be assembled in hetero-stacks or twisted Moire bilayers in which new properties may be induced, either by proximity effectsor by a Moire potential. The early results of the field spark hope of future applications of these materials in data- storage devices, lasers, infrared sensors, or as novel types of qubits. Yet, currently these studies are limited to manually fabricated single devices, which will be hard to up-scale for real-world applications. Indeed, to realize the tantalizing potential of so-called quantum materials, the development of new such species, especially in 2D, is crucial.The current pool of 2D materials suffers from two major drawbacks: First and foremost, they can be accessed only from parent van-der-Waals (vdW) materials, which limits their number; second, most 2D materials are prepared by mechanical exfoliation (colloquially known as Scotch- taping), which is impossible to scale up. In contrast, chemical exfoliation addresses both limitations: Ionic layered compounds can be chemically exfoliated by ion exchange utilizing organic solvents, thereby expanding the library of accessible 2D materials; and, chemical processing can result in alarge number of exfoliated flakes, which can then be further processed. One central goal (aim 1) of this proposed research is to establish chemical exfoliation as a method to reliably synthesize high quality, new 2D quantum materials. These sheets prepared by chemical exfoliation will be analyzed with high resolution electron microscopy and by spatially resolved spectroscopic methods. In addition, we will study electronic and magnetic properties with a wide variety of methods. New materials will have various properties, ranging from ferro- or antiferromagnetism, to frustrated magnetism, potential spin liquids, or electronic instabilities.The second aim is to synthesize new vdW materials that are not synthesizable by common methods and require kinetically controlled chemical methods. Here we will introduce new magnetically and electronically relevant vdW material as well as intrinsic heterostructures.The research proposed here represents new directions for the synthesis and investigation of 2D quantum materials. Chemical exfoliation will beestablished as a method to reliably synthesize high quality 2D crystals and novel vdW solids. The establishment of chemical exfoliation and chemical methods for the synthesis of 2D quantum materials will advance future applications, as it will allow for up-scaling of synthesis. Therefore, this is of relevance for DoD, as it brings the prospects of the field of 2D quantum matter closer to real-world applications.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 05, 2021
- Source ID
- N000142112733
Entities
People
- Leslie M Schoop
Organizations
- Office of Naval Research
- Trustees of Princeton University
- United States Navy