  The near-field interaction between fluorescent emitters and graphene exhibits
rich physics associated with local dipole-induced electromagnetic fields that
are strongly enhanced due to the unique properties of graphene. Here, we
measure emitter lifetimes as a function of emitter-graphene distance d, and
find agreement with a universal scaling law, governed by the fine-structure
constant. The observed energy transfer- rate is in agreement with a 1/d^4
dependence that is characteristic of 2D lossy media. The emitter decay rate is
enhanced 90 times (transfer efficiency of ~99%) with respect to the decay in
vacuum at distances d ~ 5 nm. This high energy-transfer rate is mainly due to
the two-dimensionality and gapless character of the monoatomic carbon layer.
Graphene is thus shown to be an extraordinary energy sink, holding great
potential for photodetection, energy harvesting, and nanophotonics.
