  We investigate the light-cone-like spread of electronic correlations in a
laser-driven quantum chain. Using the time-dependent density matrix
renormalization group, we show that high-frequency driving leads to a
Floquet-engineered spread velocity that determines the enhancement of
density-density correlations when the ratio of potential and kinetic energies
is effectively increased both by either a continuous or a pulsed drive. For
large times we numerically show the existence of a Floquet steady state at not
too long distances on the lattice with minimal heating. Intriguingly, we find a
discontinuity of dynamically scaled correlations at the edge of the light cone,
akin to the discontinuity known to exist for quantum quenches in Luttinger
liquids. Our work demonstrates the potential of pump-probe experiments for
investigating light-induced correlations in low-dimensional materials and puts
quantitative speed limits on the manipulation of long-ranged correlations
through Floquet engineering.
