Resonant enhancement of inverse photoemission transitions in bulk niobium

Publisher Website
Google Scholar
Abstract
We report the observation of the resonant enhancement of inverse photoemission transitions involving bulk band states of niobium when the energy of the transition corresponds to the plasma frequency. On resonance the cross-section increases by a factor of ∼5. Comparison with earlier reflectivity data confirms that the resonance occurs at the plasma frequency but the mearsured plasmon energy of 19.3 eV is slightly less than the 20.8 eV found in the earlier study. We do not observe resonant enhancement of transitions into surface states or interface states.