An Atomistic Insight into Moiré Reconstruction in Twisted Bilayer Graphene beyond the Magic Angle.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Twisted bilayer graphene's electronic properties depend on moiré patterns.
• Atomic reconstruction within moiré cells occurs due to interlayer interactions.
• This reconstruction is well-studied near the magic angle (1.1°).

Purpose of the Study:

• To investigate atomic reconstruction in twisted bilayer graphene at high twist angles (>1.1°).
• To explore the effect of applied strain on moiré cell evolution at these higher angles.
• To develop a method for identifying and tracking local regions within moiré cells under strain.

Main Methods:

• Theoretical and numerical analyses.
• Interpretive and fundamental physical measurements.
• Phonon behavior correlation to validate reconstruction.

Main Results:

• Atomic reconstruction is significant beyond the magic angle.
• Strain significantly impacts moiré cell evolution at high twist angles.
• A method was developed to track local moiré cell changes under strain.

Conclusions:

• Atomic reconstruction plays a vital role in moiré cell evolution at high twist angles.
• Strain engineering of moiré patterns is effective beyond the magic angle.
• Findings are crucial for advancing twistronics applications.