Photoemission Electron Microscopy for Analysis of Dielectric Structures and the Goos-Hänchen Shift

• Main Author: Stenmark, Theodore Axel
• Format: Others
• Published: PDXScholar 2016
• Subjects: Photoemission; Dielectric wave guides; Electron microscopy; Optics; Physics
• Online Access: http://pdxscholar.library.pdx.edu/open_access_etds/2991; http://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=4007&context=open_access_etds

Photoemission Electron Microscopy (PEEM) is a versatile tool that relies on the photoelectric effect to produce high-resolution electron images. Ultrafast pulse lasers allow for multi-photon PEEM where multiple visible or IR photons excite a single electron in a nonlinear process. The photoelectron yield in both cases is related to the near-field region of electromagnetic fields at the surface of the sample. We use this ability here to analyze wave propagation in a linear dielectric waveguide with wavelengths of 410 nm and 780 nm. The propagation constant of the waveguide can be extracted from interference patterns created by light propagating in the waveguide and incident light. Various properties like the polarization dependence of the propagation can be analyzed. The electromagnetic field interaction at the boundaries can then be deduced, which is essential to understand power flow in wave guiding structures. These results match well with simulations using finite element techniques as well as electromagnetic theory.