A novel way to induce ultrafast currents in molecular wires using two
incident laser frequencies, ω and 2ω, is demonstrated. The
mechanism relies on Stark shifts, instead of photon absorption, to transfer
population to the excited states and exploits the temporal profile of the field
to generate phase controllable transport. Calculations in a
\emph{trans}-polyacetylene oligomer coupled to metallic leads indicate that the
mechanism is highly efficient and robust to ultrafast electronic dephasing
processes induced by vibronic couplings.Comment: 4 pages, 2 figures, accepted to Physical Review Letter