CMSP Seminar Series @ICTP, Stasi Room, Thursday 14 February - Michele FABRIZIO

[CM Section]

Condensed Matter and Statistical Physics Seminar Series

Thursday 14 February at 11:00 a.m.
Luigi Stasi Seminar Room, first floor, Leonardo building

Michele FABRIZIO
SISSA, Trieste

'Playing with the Physics of Twisted Bilayer Graphene'

Abstract:

In this talk I will review our ongoing activity on twisted bilayer 
graphene at the first
magic angle. I will first discuss the constraints on a low energy 
description put forth
by the spatial symmetries of the Bloch wavefunction obtained through a 
realistic
tight-binding calculation performed on a relaxed structure.

Next I will propose a minimal tight-binding model that reproduces the 
elementary
band representation of the emergent P622 low-energy space group.

Finally, I will show how the emergent symmetry shows up in the phonon 
spectrum,
which suggests the intriguing possibility of an Exe Jahn-Teller effect 
as a possible
mechanism to split the so-called valley degeneracy.