Graphene as the Model Low-Dimensional Photogalvanic Material

In this chapter, we will briefly review optoelectronic properties of graphene, especially photocurrent as a function of light wavelength and intensity with light being unpolarized or in fixed linear polarization state. Then, we will provide necessary knowledge about the band structure, crystal symmetry, and geometric properties of graphene related to second-order response, particularly the most important information related to photocurrent due to the photogalvanic effect together with the photon drag effect. This will include the simple phenomenology upon linearly and circularly polarized irradiation at normal and oblique incidence.