Strain-Induced Quantum Phase Transitions in Magic-Angle Graphene
نویسندگان
چکیده
We investigate the effect of uniaxial heterostrain on interacting phase diagram magic-angle twisted bilayer graphene. Using both self-consistent Hartree-Fock and density-matrix renormalization group calculations, we find that small strain values (??0.1%–0.2%) drive a zero-temperature transition between symmetry-broken “Kramers intervalley-coherent” insulator nematic semimetal. The critical lies within range experimentally observed values, therefore predict is at least partly responsible for sample-dependent experimental observations.Received 11 January 2021Accepted 30 May 2021DOI:https://doi.org/10.1103/PhysRevLett.127.027601© 2021 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasCharge orderPhase transitionsPhysical SystemsGrapheneHoneycomb latticeStrongly correlated systemsTwo-dimensional electron systemTechniquesDensity matrix groupHartree-Fock methodsMatrix product statesCondensed Matter, Materials & Applied Physics
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2021
ISSN: ['1079-7114', '0031-9007', '1092-0145']
DOI: https://doi.org/10.1103/physrevlett.127.027601