Light controlled THz plasmonic time varying media: momentum gaps, entangled plasmon pairs, and pulse induced time reversal

This letter establishes a Floquet engineering framework in which coherent high frequency light with a time dependent amplitude can be used to parametrically excite and amplify THz plasmons, mirror plasmonic wave packets in time, generate momemtum-gapped plasmonic band structures, entangled plasmon pairs, and THz radiation in two dimensional Dirac systems. Our results show how low frequency plasmons can be coherently excited and manipulated without the need for THz light.