title: Anomalous nonlinear absorption in epsilon-near-zero materials: optical limiting and all-optical control.
abstract: We investigate nonlinear absorption in films of epsilon-near-zero materials. The combination of large local electric fields at the fundamental frequency and material losses at the harmonic frequencies induce unusual intensity-dependent phenomena. We predict that the second-order nonlinearity of a low-damping, epsilon-near-zero slab produces an optical limiting effect that mimics a two-photon absorption process. Anomalous absorption profiles that depend on low permittivity values at the pump frequency are also predicted for third-order nonlinearities. These findings suggest new opportunities for all-optical light control and novel ways to design reconfigurable and tunable nonlinear devices.
authors.forename: M A
authors.initials: MA
authors.lastname: Vincenti
authors.forename: D
authors.initials: D
authors.lastname: de Ceglia
authors.forename: Michael
authors.initials: M
authors.lastname: Scalora