Interference between 3D → 3D electron-exchange transitions and interband excitations in MnO(100)

• Published in: Solid state communications Vol. 82; no. 11; pp. 879 - 882
• Main Authors: Jeng, Shin-Puu, Henrich, Victor E.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.06.1992; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron and ion emission by liquids and solids; impact phenomena; Exact sciences and technology; Impact phenomena (including electron spectra and sputtering); Other electron-impact emission phenomena; Physics; Electron energy loss spectrum; Exchange interaction; Interference; Manganese Oxides; Electronic transition; Multiplet state; Experimental study; Inorganic compound
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/0038-1098(92)90712-I

We report the observation of strong optically forbidden 3d → 3d transitions in the electron-energy-loss spectra of vacuum-cleaved MnO(100). A striking sensitivity of the relative amplitudes of the various 3d → 3d multiplet transitions to the interference from other excitation channels is observed for the first time in the transition-metal oxides. A model reflecting the electron exchange nature of the 3d → 3d transition in MnO, similar to that used to describe the 4f → 4f transitions in rare-earth metals, is proposed to explain the large amplitudes of the transitions. However, unlike the case of the rare-earth metals, the energy dependence of the amplitude of the transitions cannot be explained simply in terms of a resonant electron emission process.