Resonant inverse photoemission: A new probe of correlated systems

Abstract

Inverse photoemission measurements of cerium compounds reveal a strong energy dependence near the Ce ${\mathit{M}}_{5}$ (3${\mathit{d}}_{5/2}$\ensuremath{\rightarrow}4f) absorption edge. Two separate resonances, resulting from configuration mixing in the ground state, are identified for the first time. Their relative intensities reflect the different hybridization strengths in various Ce-based materials. Because of its site and symmetry selectivity, resonant inverse photoemission is potentially a valuable technique for the investigation of correlated materials, complementary to the well-established resonant photoemission spectroscopy.