  In the field of condensed matter, graphene plays a central role as an
emerging material for nanoelectronics. Nevertheless, graphene is a semimetal,
which constitutes a severe limitation for some future applications. Therefore,
a lot of efforts are being made to develop semiconductor materials whose
structure is compatible with the graphene lattice. In this perspective, little
pieces of graphene represent a promising alternative. In particular, their
electronic, optical and spin properties can be in principle controlled by
designing their size, shape and edges. As an example, graphene nanoribbons with
zigzag edges have localized spin polarized states. Likewise, singlet-triplet
energy splitting can be chosen by designing the structure of graphene quantum
dots. Moreover, bottom-up molecular synthesis put these potentialities at our
fingertips. Here, we report on a single emitter study that directly addresses
the intrinsic properties of a single graphene quantum dot. In particular, we
show that graphene quantum dots emit single photons at room temperature with a
high purity, a high brightness and a good photostability. These results pave
the way to the development of new quantum systems based on these nanoscale
pieces of graphene.
