# Floquet-engineered light-cone spreading of correlations in a driven quantum chain

## TL;DR

This paper explores how high-frequency laser driving can control the spread of electronic correlations in a quantum chain, revealing Floquet-engineered light-cone dynamics and steady states with minimal heating.

## Contribution

It demonstrates the Floquet engineering of correlation spread velocities and the existence of Floquet steady states in a driven quantum chain, with implications for controlling correlations in low-dimensional materials.

## Key findings

- High-frequency driving enhances correlation spread velocity.
- Existence of Floquet steady states with minimal heating.
- Discontinuity in scaled correlations at the light cone edge.

## Abstract

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.