In the paper I am reading, it was written that "The dynamic conductivity of graphene could elucidate features that would demonstrate unique properties of this system and allow for the identification of characteristic energy scales associated with the band structure." I couldn't really get what is meant by "THE DYNAMIC CONDUCTIVITY" and how it differs from the conductivity we usually use? what types of conductivity are there?
paper: Electronic properties of graphene-based bilayer systems https://arxiv.org/abs/1511.06706
