9.4 Physical Properties of Materials (PECASE): Synthesis and Fundamental Studies of Atomic Layers, Atomic Quilts, and van der Waals Heterostructures
Abstract
Two-dimensional (2D) crystalline nanomaterials consisting of one or few atomic layers with interlayer van der Waals (vdW) interaction have captivated the scientific and public imagination with the plethora of novel phenomena, new understanding, and new ideas that span diverse disciplines in the physical sciences. Graphene, the prototypical 2D atomic sheet has been largely responsible for the great interest over the last decade in basic and applied research studies with new profound insights into condensed matter systems. Recently, there has been rapidly growing interest to uncover and investigate other 2D atomic layers that can be found in nature or synthesized, which include hexagonal boron nitride (hBN), the transitional metal dichalcogenides (TMD), and the column IV atomic sheets (silicene, germanene). Invariable, these 2D atomic layers can potentially offer a broader wealth of understanding and phenomena beyond what has been uncovered in graphene. Examples of new phenomena include memory effect, quantum-spin Hall effect, electro-optic effects, and piezomagnetism in silicene, and correlated and various single-particle states in bulk TMDs that might be greatly enhanced in the 2D monolayer limit. However, the synthesis of high-quality large-area atomic layers represents the biggest barrier to broad research inquiry to discover new paradigms, investigate novel phenomena, and assess properties for advanced defense sciences and technologies. In this light, this research effort proposes the synthesis of new crystalline 2D atomic layers that combined enables the proposed innovative effort on the in-situ synthesis of single-layer atomic quilts, and van der Waals heterogeneous layered compounds. The synthesized atomic and compound sheets can be released from the growth substrate to realize free-standing layers that can be draped on arbitrary surfaces. The research effort consists of three thrusts over the five year duration. Thrust I: Homogeneous Material Synthesis. This thrust is focused on the synthesis of monolayer and few layers of crystalline atomic sheets. Chemical vapor deposition of silicene, a universal route for growing semiconducting TMDs, synthesis of n-dimensional hBN, and the single-crystal epitaxial growth of mono and few layers of rare-earth pnictides constitute the creative approaches taken in this thrust. Thrust II: 2D Binary Atomic Quilts. The proposed thrust is a pioneering initiative to create atomic quilts or mosaics of random or ordered patterns. The driving hypothesis is that the whole is greater than the sum of the parts. Thrust III: Understanding Defects for Non-volatile Resistive Switching in 2D Monolayers. This thrust will conduct basic experimental studies on exploiting defects for resistive switching in TMD monolayers based on our recent discovery. Synthetic monolayers and advanced characterization tools will be employed to elucidate the nature and density of defects and its role in producing resistive switching.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 29, 2019
- Source ID
- W911NF1610277
Entities
People
- Deji Akinwande
Organizations
- Army Contracting Command
- United States Army
- University of Texas at Austin