Chiral Interlayer Rotations for Atomically-Thin Layered Metamaterials
Abstract
The interlayer rotation angle is an exciting new degree of freedom in 2D layered materials (2DLMs), and its precise control has recently produced metamaterials including van der Waals moire crystals with many emergent phenomena that are not found in nature. As these 2DLM multilayers with non-zero interlayer rotations are not thermodynamically preferred in growth, they must be made artificially layer-by-layer with single layer building blocks with a predetermined lattice orientation. The main aim of this project is to develop atomically thin metamaterials based on 2DLMs with tunable physical properties by precisely programing the interlayer structures in their multilayer stacks. There are significant materials issues that need to be addressed in order to produce multilayer stacks and 2DLM-based films that are contamination-free and fully controlled. This final report describes the development and application of the new synthesis, fabrication, characterization techniques our group has developed for studying fundamental structural and optical properties in 2D materials, including mono- and multi-layers of transition metal dichalcogenides (TMDs) and their molecular analogs, as funded by the AFOSR grant (FA9550-16-1-0347). First, we have developed approaches to grow high quality monolayer TMDs with precisely controlled electronic properties. This includes the synthesis of coherent lateral WS2/WSe2 superlattices with defect free interfaces and MoS2 monolayers with substitutional Nb-dopants. Second, we have developed fabrication and stacking approaches that are optimized for TMD films with pristine interfaces. This includes a new resist-free lithography method and robotic 4D pixel assembly that automatically stacks TMD based pixels with high throughput. Third, we have discovered and tuned novel optical properties of TMD films and stacks.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 04, 2022
- Accession Number
- AD1230649
Entities
People
- Jiwoong Park
Organizations
- University of Chicago