Speaker
Prof.
Igor Herbut
(Simon Fraser University)
Description
I will review the recent work on the phases and quantum phase transitions in the electronic systems that feature the parabolic band touching at the Fermi level, the celebrated and well-studied example of which is the bilayer graphene. In particular, it will be argued that such three-dimensional systems are in principle unstable towards the spontaneous formation of the (topological) Mott insulator at weak long-range Coulomb interaction. The mechanism of the instability can be understood as the collision of non-Fermi liquid fixed point, discovered by Abrikosov in the `70s, with another, critical, fixed point, which approaches it in the coupling space as the system's dimensionality reaches certain ``critical dimension" from above. Some universal characteristics of this scenario, the width of the non-Fermi liquid crossover regime, and the observability of the nematic Mott phase in common gapless semiconductors such as gray tin or mercury tellurude will be discussed.
Author
Prof.
Igor Herbut
(Simon Fraser University)
