Special CPM Seminar

Why does graphene behave as a weakly interacting system?

Sankar Das Sarma

University of Maryland

Graphene is a special two-dimensional version of quantum electrodynamics with the coupling constant (i.e. the effective graphene fine-structure constant) being around 2 rather than 1/137. Nevertheless, graphene seems to behave as a weak-coupling interacting system from the experimental perspective. Why? I will describe our systematic efforts [1-3] in trying to solve this fundamental mystery. I will discuss both theory and experiment in this particular context.

[1] S. Das Sarma and E.H. Hwang, Phys. Rev. B 87, 045425 (2013)
[2] E. Barnes et al., Phys. Rev. B 89, 235431 (2014)
[3] J. Hofmann et al., Phys. Rev. Lett. 113, 105502 (2014)