Ultrafast Dynamic Metallization of Dielectric Nanofilms by Strong   Single-Cycle Optical Fields
  We predict a dynamic metallization effect where an ultrafast (single-cycle) optical pulse with a field less or on the order of 1 V/Angstrom causes plasmonic metal-like behavior of a dielectric film with a few-nm thickness. This manifests itself in plasmonic oscillations of polarization and a significant population of the conduction band evolving on a femtosecond time scale. These phenomena are due a combination of both adiabatic (reversible) and diabatic (for practical purposes irreversible) pathways. 
Maxim Durach, Anastasia Rusina, Matthias F. Kling, and Mark I.   Stockman
cond-mat.mes-hall physics.optics