Controlling Electric Field and Photoemission at the Tips of Triangular Gold Antennas

We show that the fields of surface plasmon polaritons (SPPs)—excited by infrared ultrafast laser light—can be highly concentrated at the corners of thin, micron-scale gold triangular platelets. We present multi-photon photoemission electron microscopy (nP-PEEM) images and finite element method (FEM) simulations that show that the magnitude of the SPP electric field can be adjusted over a large range via control of the polarization, wavelength, and angle of incidence of the applied laser light. As it is well known that the strength of SPP near-fields has a strong bearing on non-linear photoelectron emission rates, localized SPP fields might effectively be used as a nano-scale adjustable electron source.