Abstract
We investigate the bandwidth compression due to out of plane pressure of the moiré flatbands near charge neutrality in twisted bilayer graphene for a continuous range of small rotation angles of up to 2.5 . The flatband bandwidth minima angles are found to grow linearly with interlayer coupling ω and decrease with Fermi velocity. Application of moderate pressure values of up to 2.5 GPa achievable through a hydraulic press should allow to access a flatband for angles as large as 1.5 instead of 1 at zero pressure. This reduction of the moiré pattern length for larger twist angles implies increase of the effective Coulomb interaction scale per moiré cell by about 50% and enhances roughly by a factor of 2 the elastic energy that resists the commensuration strains due to the moiré pattern. Our results suggest that application of pressure on twisted bilayer graphene nanodevices through a hydraulic press will notably facilitate the device preparation efforts required for exploring the ordered phases near magic angle flatbands.
Original language | English |
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Article number | 015001 |
Journal | Electronic Structure |
Volume | 1 |
Issue number | 1 |
DOIs | |
State | Published - Mar 2019 |
Keywords
- Electronic structure
- Flatbands
- Moire patterns
- Pressure
- Twisted bilayers