This research was supported by the Basic Science Office of the Department of Energy under grant no. DE-FG02-07ER46406.
Photoemission, Surface plasmon resonance, Nanostructures, Electron microscopes
Photoemission Electron Microscopy (PEEM) is a versatile tool that relies on the photoelectric effect to produce high-resolution images. Pulse lasers allow for multi-photon PEEM where multiple photons are required excite a single electron. This non-linear process can directly image the near field region of electromagnetic fields in materials. We use this ability here to analyze wave propagation in a linear dielectric waveguide with wavelengths of 410nm and 780nm. The propagation constant of the waveguide can be extracted from the interference pattern created by the coupled and incident light and shows distinct polarization dependence. 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.
Stenmark, T., Word, R. C., & Könenkamp, R. (2016). Determination of the Goos-Hänchen shift in dielectric waveguides via photo emission electron microscopy in the visible spectrum. Optics Express, 24(4), 3839–48.