Quantum Field Theory Approach to the Optical Conductivity of Strained and Deformed Graphene

Abstract

The computation of the optical conductivity of strained and deformed graphene is discussed within the framework of quantum field theory in curved spaces. The analytical solutions of the Dirac equation in an arbitrary static background geometry for one dimensional periodic deformations are computed, together with the corresponding Dirac propagator. Analytical expressions are given for the optical conductivity of strained and deformed graphene associated with both intra and interbrand transitions. The special case of small deformations is discussed and the result compared to the prediction of the tight-binding model.

Signature of curved QFT effects on the optical properties of deformed graphene

“…We would like to mention that the effects of in-plane deformations associated to strain and out-of-the plane deformations on the optical conductivity of graphene-like materials, within the formalism of a Dirac equation in curved space, were explored in ref. [51]. In our analysis of the experimental results, the contributions of in-plane deformations and of possible changes in the Fermi velocity of the electrons are not taken into account.…”

Two Dimensional Honeycomb Materials: Random Fields, Dissipation and Fluctuations

“…From the technological point of view, the understanding on how the electronic properties of graphene change due to defects, impurities, sources of disorder, or deformations is crucial-see, e.g., [6][7][8] and references therein. In graphene, there are many possible sources of disorder such as the presence of charged impurities of the substrate, of resonant scatters, of structural defects, of strain fluctuations just to name a few.…”