Abstract

Plasmonic enhancement of optical near-fields at nanostructures provides for localization of the energy of light on the nanoscale. This phenomenon allowed pioneering applications in spectroscopy, photovoltaics and sensorics. It remains a challenge to measure the extent of the maximum achievable nanoplasmonic field enhancement for a particular sample. Even though near-field probing methods such as scanning near-field optical microscopy (SNOM) can reach a resolution down to 8-10 nm, probing near-fields on ~1 nm scale needs a different approach. Here, we demonstrate a method for nanoplasmonic near-field measurement with the help of photoemitted electrons induced by femtosecond laser pulses.

© 2017 IEEE