Ultrafast switching of photoemission by polarization modulation in a metallic plasmonic nanostructure

Abstract Steering photoelectrons in a well-defined spatiotemporal localization is realized by exciting with incident one-color double-pulses. We demonstrate active control of the photoemission yield for various plasmonic hot spots by tuning the polarization direction of the two orthogonally polarized laser pulses. The polarization of the pulse pair changes the plasmonic field response, corresponding to their interaction with the plasmonic hot spot. A model describes the modulation depth of the photoemission yield as a function of the difference of the photoemission response to the incident two laser pulses. Moreover, our results reveal that the proportion of photoemission yields is mainly determined by the rearrangement of the quantum pathway proportion.