Non‐Linear Optics at Twist Interfaces in h‐BN/SiC Heterostructures
Abstract
Understanding the emergent electronic structure in twisted atomically thin layers has led to the exciting field of twistronics. However, practical applications of such systems are challenging since the specific angular correlations between the layers must be precisely controlled and the layers have to be single crystalline with uniform atomic ordering. Here, an alternative, simple, and scalable approach is suggested, where nanocrystallinetwo‐dimensional (2D) film on 3D substrates yields twisted‐interface‐dependent properties. Ultrawide‐bandgap hexagonal boron nitride (h‐BN) thin films are directly grown on high in‐plane lattice mismatched wide‐bandgap silicon carbide (4H‐SiC) substrates to explore the twist‐dependent structure‐property correlations. Concurrently, nanocrystalline h‐BN thin film shows strong non‐linear second‐harmonic generation and ultra‐low cross‐plane thermal conductivity at room temperature, which are attributed to the twisted domain edges between van der Waals stacked nanocrystals with random in‐plane orientations. First‐principles calculations based on time‐dependent density functional theory manifest strong even‐order optical nonlinearity in twisted h‐BN layers. This work unveils that directly deposited 2D nanocrystalline thin film on 3D substrates could provide easily accessible twist‐interfaces, therefore enabling a simple and scalable approach to utilize the 2D‐twistronics integrated in 3D material devices for next‐generation nanotechnology.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 19, 2023
- Source ID
- 10.1002/adma.202304624
Entities
People
- A. Glen Birdwell
- Abhijit Biswas
- Anand B Puthirath
- Bradford B. Pate
- Chenxi Li
- Elias J. Garratt
- Gustavo A. Alvarez
- Hanyu Zhu
- Harikishan Kannan
- Jacob Elkins
- Jin Zhang
- Jordan A Hachtel
- Joyce Christiansen‐Salameh
- Kory Burns
- Mahesh R. Neupane
- Pulickel Ajayan
- Robert Vajtai
- Rui Xu
- Sathvik Ajay Iyengar
- Tao Li
- Tia Gray
- Tony Ivanov
- Tymofii S. Pieshkov
- Xiang Zhang
- Yuji Zhao
- Zhiting Tian
- Ángel Rubio Secades
Organizations
- Army Research Office
- Center for Free-Electron Laser Science
- Cornell University
- Flatiron Institute
- German Research Foundation
- National Natural Science Foundation of China
- Oak Ridge National Laboratory
- Office of Basic Energy Sciences
- Office of Science
- Rice University
- Robert A. Welch Foundation
- United States Department of Energy
- United States Naval Research Laboratory
- University of Virginia