Compact extreme ultraviolet source for laboratory-based photoemission spectromicroscopy

We report on the combination of a state-of-the-art energy-filtering photoemission electron microscope with an intense yet compact laboratory-based gas discharge extreme ultraviolet (EUV) light source. Using a photon energy of 71.7 eV from oxygen plasma (O5+ spectral line), we demonstrate element-selective photoelectron imaging in real space and band structure mapping in reciprocal space. Additionally, the high surface sensitivity of the EUV light was used to study the surface oxidation on islands of the phase-change material Ge1Sb2Te4. The EUV light source allows the extension of spectromicroscopy, previously only feasible at synchrotron beamlines, to laboratory-based work.