  The perfect transmission of charge carriers through potential barriers in
graphene (Klein tunneling) is a direct consequence of the Dirac equation that
governs the low-energy carrier dynamics. As a result, localized states do not
exist in unpatterned graphene, but quasi-bound states \emph{can} occur for
potentials with closed integrable dynamics. Here, we report the observation of
resonance states in photo-switchable self-assembled molecular(SAM)-graphene
hybrid. Conductive AFM measurements performed at room temperature reveal strong
current resonances, the strength of which can be reversibly gated \textit{on-}
and \textit{off-} by optically switching the molecular conformation of the
mSAM. Comparisons of the voltage separation between current resonances ($\sim
70$--$120$ mV) with solutions of the Dirac equation indicate that the radius of
the gating potential is $\sim 7 \pm 2$ nm with a strength $\geq 0.5$ eV. Our
results and methods might provide a route toward \emph{optically programmable}
carrier dynamics and transport in graphene nano-materials.
