Optical response in twisted bilayer graphene

There has been a lot of focus on the electronic properties of twisted bilayer graphene (TBG), but also the related optical response can be used to discuss basic phenomena. E.g., the observed superconductivity can be characterized via the Drude weight that can be measured e.g. via scattering-type scanning near-field optical microscopy. Here, I will report on the optical response of TBG as it is obtained from an atomistic tight-binding model including lattice relaxation. By including interaction effects within the Hartree-Fock approximation [1], we interprete the corrections to the renormalization of the Fermi velocity. Apart from the charge response, we will also calculate the magnetic and chiral response [2]. Last, the shift current and Berry curvature dipole shall be discussed.