  Plasmonics can be used to improve absorption in optoelectronic devices and
has been intensively studied for solar cells and photodetectors. Graphene has
recently emerged as a powerful plasmonic material. It shows significantly less
losses compared to traditional plasmonic materials such as gold and silver and
its plasmons can be tuned by changing the Fermi energy with chemical or
electrical doping. Here we propose the usage of graphene plasmonics for light
trapping in optoelectronic devices and show that the excitation of localized
plasmons in doped, nanostructured graphene can enhance optical absorption in
its surrounding media including both bulky and two-dimensional materials by
tens of times, which may lead to a new generation of highly efficient,
spectrally selective photodetectors in mid-infrared and THz ranges. The
proposed concept could even revolutionize the field of plasmonic solar cells if
graphene plasmons in the visible and near-infrared are realized.
