Optical beam shifts in graphene and single-layer boron-nitride

Optical beam shifts from a freestanding 2D atomic crystal are investigated. In contrast with a 3D crystal, the magnitude of the Goos-Hänchen shift depends on the surface susceptibility of the crystal and not on the wavelength of the incident light beam. The surface conductivity of the atomically thin crystal is less important in this context because it enters in the expression of the shifts only as a second-order parameter. In analogy to a 3D crystal, the magnitudes of the Imbert-Fedorov shift and of the angular shifts depend, respectively, on the wavelength and on the square of the beam angular aperture.