Resonance photoelectron spectroscopy using a tunable laser plasma light source

Abstract

We report the first resonance photoemission experiments on plutonium metal, with surface preparation accomplished by means of laser ablation. The photoemission experiments were conducted using the newly commissioned tunable light source for transuranic research at Los Alamos. The light source is a tunable, laser plasma system capable of producing photons in the energy range 30–150 eV, with a photon flux of order 109 photons s−1 at 0.1% bandwidth. First results on δ-phase plutonium reveal the 5d–5f resonance enhancement to be maximum at a photon energy of 113 eV. Lower energy photoemission results show a narrow peak very near the Fermi level, with a linewidth of order 100 meV. This peak is verified by resonance photoemission to be of 5f character but also having strong 6d–7s contributions. The combination of high-energy resolution, tunable energies for orbital character determination and surface sensitivity of the UPS energy range make the laser plasma light source ideal for surface and interface studies. © 1998 John Wiley & Sons, Ltd.