  Realizing graphene's promise as an atomically thin and tunable platform for
fundamental studies and future applications in quantum transport requires the
ability to electrostatically define the geometry of the structure and control
the carrier concentration, without compromising the quality of the system.
Here, we demonstrate the working principle of a new generation of high quality
gate defined graphene samples, where the challenge of doing so in a gapless
semiconductor is overcome by using the $\nu=0$ insulating state, which emerges
at modest applied magnetic fields. In order to verify that the quality of our
devices is not compromised by the presence of multiple gates we compare the
electronic transport response of different sample geometries, paying close
attention to fragile quantum states, such as the fractional quantum Hall (FQH)
states, that are highly susceptible to disorder. The ability to define local
depletion regions without compromising device quality establishes a new
approach towards structuring graphene-based quantum transport devices.
