▎ 摘 要
Using effective medium theory, spatial and angular Goos-Hanchen and Imbert-Fedorov reflection shifts of a graphene-coated granular substrate composed of non-spherical gold nanoparticles in a dielectric host are investigated. The numerical results indicate that the composite substrate can play a role in tunability of shifts similar to that of an electrically-controlled graphene layer does. It is realized that both shape and volume fraction of granular inclusions can bring about a broad shift modulation. This may provide applications in nano-optics as well as in characterizing the parameters of the composite.