  A seminal gedankenexperiment by Laughlin describes the charge transport in
quantum Hall systems via the pumping of flux. Here, we propose an optical
scheme which probes and manipulates quantum Hall systems in a similar way: When
light containing orbital angular momentum interacts with electronic Landau
levels, it acts as a flux pump which radially moves the electrons through the
sample. We investigate this effect for a graphene system with Corbino geometry,
and calculate the radial current in the absence of any electric potential bias.
Remarkably, the current is robust against disorder, and in the weak excitation
limit, the current shows a power-law scaling with intensity characterized by
the novel exponent 2/3.
