Symmetry breaking and Chern insulators in twisted graphene structures

Rövid cím: 
Chern insulators in twisted graphene
Időpont: 
2021. 11. 26. 10:15
Hely: 
BME building F, seminar room of the Dept. of Theoretical Physics
Előadó: 
Louk Rademaker (Geneve)
Talk also broadcasted online in Teams. Please write to asboth.janos@ttk.bme.hu for the Teams link.  
 
Twisted bilayer graphene (tBG) and variants like twisted monolayer-bilayer graphene (tMBG) were proposed to be a platform for strongly correlated physics akin to the cuprate family. However, I will show that many of the observed interacting phenomena can be explained in terms of breaking of spin/valley symmetry. This can lead to a quantum anomalous Hall effect in the absence of a field, as I will show for tMBG [1]. In large magnetic fields the same spin- valley symmetry breaking leads to a series of Chern insulator states [2]. Finally, I will briefly discuss the possibility of genuine strong correlated physics in Moiré structures.
 
[1] Rademaker, Protopopov, Abanin, Phys. Rev. Research, 2, 033150 (2020).
[2] Saito, Ge, Rademaker, Watanabe, Taniguchi, Abanin, Young, Nature Physics, 108, 12233 (2021).