  Two-dimensional van der Waals heterostructures can be engineered into
artificial superlattices that host flat bands with significant Berry curvature
and provide a favorable environment for the emergence of novel electron
dynamics. In particular, the Berry curvature can induce an oscillating
trajectory of an electron wave packet transverse to an applied static electric
field. Though analogous to Bloch oscillations, this novel oscillatory behavior
is driven entirely by quantum geometry in momentum space instead of band
dispersion. While the orbits of Bloch oscillations can be localized by
increasing field strength, the size of the geometric orbits saturates to a
nonzero plateau in the strong-field limit. In non-magnetic materials, the
geometric oscillations are even under inversion of the applied field, whereas
the Bloch oscillations are odd, a property that can be used to distinguish
these two co-existing effects.
