Floquet engineering of correlated states by the Ponderomotive potential

The Ponderomotive force is a second order DC force that a particle feels in an inhomogenenous AC field. The effective potential for this force may be called the Ponderomotive potential. We generalize the notion of Ponderomotive potential to periodically driven systems and propose it as a convenient tool to engineer their properties beyond the single particle level. For example, the Ponderomotive potential from coherent incident light may be used to selectively enhance or suppress excitonic order and charge/spin density wave, to steer order parameters between (almost) degenerate states, and to generate interactions on demand such as attractive ones.