  In two-dimensional artificial crystals with large real-space periodicity, the
nonlinear current response to a large applied electric field can feature a
strong angular dependence, which encodes information about the band dispersion
and Berry curvature of isolated electronic Bloch minibands. Within the
relaxation-time approximation, we obtain analytic expressions up to infinite
order in the driving field for the current in a band-projected theory with
time-reversal and trigonal symmetry. For a fixed field strength, the dependence
of the current on the direction of the applied field is given by rose curves
whose petal structure is symmetry constrained and is obtained from an expansion
in real-space translation vectors. We illustrate our theory with calculations
on periodically-buckled graphene and twisted double bilayer graphene, wherein
the discussed physics can be accessed at experimentally-relevant field
strengths.
