Local and Global Directionality Patterns of Electron Photoemission from Plasmonic Nanoparticles

Concepts of local and global photoemission directivity patterns are introduced for plasmonic nanoparticles of arbitrary shape, and the relationship between them is established. Formulas for the local photoemission directionality pattern for surface and volume photoemission mechanisms are obtained for a given field distribution in plasmonic modes inside nanoparticles of arbitrary shape. As an illustration of the theory, the local and global photoemission patterns are calculated for spherical nanoparticles with excited dipole or quadruple plasmonic modes. It is shown that the patterns resulting from the surface and volume photoemission differ qualitatively as well as the patterns produced by various plasmonic modes. The findings can be useful in various plasmonic applications, namely, nanostructured photocathodes, photodetectors, in plasmonic photocatalysis, and others.

Automated summary

The concepts of local and global photoemission directivity patterns for plasmonic nanoparticles of arbitrary shape are introduced, and their relationship is established. Formulas for the local photoemission directionality pattern are obtained for different mechanisms and field distributions in plasmonic modes inside nanoparticles. The calculated patterns for spherical nanoparticles with excited dipole or quadruple plasmonic modes show qualitative differences between surface and volume photoemission, and also among different plasmonic modes. These findings have potential applications in various plasmonic devices and technologies, including nanostructured photocathodes, photodetectors, and plasmonic photocatalysis.