| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
2D Materials: Preparation, Properties, Modeling & Applications
|
| Presentation Title |
Mapping the Local and Global Vibrational Properties of Hetero-strained Twisted Bilayer Graphene |
| Author(s) |
Hesam Askari, Aditya Dey, Shoieb Ahmed Chowdhury |
| On-Site Speaker (Planned) |
Hesam Askari |
| Abstract Scope |
Fabrication of twisted bilayer graphene has led to many fascinating properties that are strongly correlated with the periodically repeating pattern in its structure. Within each pattern, inter-layer interactions cause reconfiguration of atoms in each layer and form sub-regions with unique stacking. While this phenomenon has been extensively studied using experimental and computational methods for angles close to the threshold angle ~1.1 degrees, the extent of reconstruction for higher angles is unclear. In addition, the correlation of local domains and their contribution to the global properties is yet to be understood. We use atomistic-level analyses to identify these local regions and track their formation and evolution with strain using interpretive and fundamental physical measures. We show that optical phonon modes and Raman signatures is particularly tied to that of the AB-stacking. Furthermore, we report validated evidence of structural reconstruction for larger twist angles and quantify the extent of reconstruction. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Thin Films and Interfaces, Modeling and Simulation |