Optical near-field interference in the excitation of a bowtie nanoantenna

We show experimentally as well as in simulation that the phase-sensitive superposition of different plasmonic modes leads to a spatially controllable enhancement of the near-field inside and in the vicinity of a metallic nanostructure. Multiphoton photoemission electron microscopy maps the local near-field distribution. By controlling the relative phase Θ between two orthogonally polarized light pulses the spatial distribution of the near-field is manipulated on the basis of the interference of the near-field modes. This demonstration of optical near-field control is corroborated by finite integral time domain calculations.