  The extreme mechanical resilience of graphene and the peculiar coupling it
hosts between lattice and electronic degrees of freedom have spawned a strong
impetus towards strain-engineered graphene where, on the one hand, strain
augments the richness of its phenomenology and makes possible new concepts for
electronic devices and, on the other hand, new and extreme physics might take
place. Here, we demonstrate that the shape of substrates supporting graphene
sheets can be optimized for approachable experiments where strain-induced
pseudomagnetic fields (PMF) can be tailored by pressure for directionally
selective electronic transmission and pinching-off of current flow down to the
quantum channel limit. The Corbino-type layout explored here furthermore allows
filtering of charge carriers according to valley and current direction, which
can be used to inject or collect valley-polarized currents, thus realizing one
of the basic elements required for valleytronics. Our results are based on a
framework developed to realistically determine the combination of strain,
external parameters, and geometry optimally compatible with the target spatial
profile of a desired physical property --- the PMF in this case. Characteristic
conductance profiles are analyzed through quantum transport calculations on
large graphene devices having the optimal shape.
