  We report on Coulomb blockade and Coulomb diamond measurements on an etched,
tunable single-layer graphene quantum dot. The device consisting of a graphene
island connected via two narrow graphene constrictions is fully tunable by
three lateral graphene gates. Coulomb blockade resonances are observed and from
Coulomb diamond measurements a charging energy of ~3.5 meV is extracted. For
increasing temperatures we detect a peak broadening and a transmission increase
of the nanostructured graphene barriers.

Mesoscale and Nanoscale Physics