Nanoscale imaging of local few-femtosecond near-field dynamics within a single plasmonic nanoantenna.
The local enhancement of few-cycle laser pulses by plasmonic nanostructures opens up for spatiotemporal control of optical interactions on a nanometer and few-femtosecond scale. However, spatially resolved characterization of few-cycle plasmon dynamics poses a major challenge due to the extreme length and time scales involved. In this letter, we experimentally demonstrate local variations in the d