Strain-Induced Quantum Phase Transitions in Magic-Angle Graphene
Abstract
We investigate the effect of uniaxial heterostrain on the interacting phase diagram of magic-angle twisted bilayer graphene. Using both self-consistent Hartree-Fock and density-matrix renormalization group calculations, we find that small strain values (ε ∼0.1 %- 0.2 % ) drive a zero-temperature phase transition between the symmetry-broken "Kramers intervalley-coherent" insulator and a nematic semimetal. The critical strain lies within the range of experimentally observed strain values, and we therefore predict that strain is at least partly responsible for the sample-dependent experimental observations.
- Publication:
-
Physical Review Letters
- Pub Date:
- July 2021
- DOI:
- 10.1103/PhysRevLett.127.027601
- arXiv:
- arXiv:2012.09885
- Bibcode:
- 2021PhRvL.127b7601P
- Keywords:
-
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- Phys. Rev. Lett. 127, 027601 (2021)