Micrometer-scale band mapping of single silver islands in real and reciprocal space

Although ultraviolet photoelectron emission spectroscopy and microscopy have served as powerful tools for electronic structure analysis in both reciprocal and real space, the integration of spectroscopy into microscopy still remains a challenge due to the technical difficulty of achieving both high spatial and energy resolution with slow electrons. We demonstrate photoelectron emission spectroscopy and microscopy covering the real, reciprocal, and energy spaces efficiently, enabled by a recently developed energy-filtered microscope. Observation of photoemission from micron-sized silver islands using He I radiation reveals the importance of the unreduced final-state wave vectors, which determine the photoelectron angular distribution.