  We introduce an all-optical approach to producing high-flux synthetic
magnetic fields for neutral atoms or molecules by designing intrinsically
time-periodic optical superlattices. A single laser source, modulated to
generate two frequencies, suffices to create dynamically modulated interference
patterns which have topological Floquet energy bands. In particular, we propose
a simple laser setup that realizes a tight-binding model with uniform flux per
plaquette and well-separated Chern bands. Our method relies only on the
particles' scalar polarizability and far detuned light.
