Ultrafast electronic processes in an insulator: The Be and O sites in BeO

[摘要] The short-time dynamics of amorphous beryllium oxide (a-BeO) has been investigated for electronic excitation/ionization by fast incident electrons, as well as by Ar7+, Ar15+, Xe15+, and Xe31+ ions at velocities of 6-10% the speed of light. Site specific Auger-electron spectra induced by fast heavy ions are the central point of this investigation. Electron induced Auger spectra serve as a reference and electron-energy loss (EELS) spectroscopy as well as resonant inelastic X-ray scattering (RIXS) are invoked for quantitative understanding. For the heavy-ion case, we observe strong variations in the corresponding spectral distributions of Be-K and O-K Auger lines. These are related to local changes of the electron density, of the electron temperature and even of the electronic band structure of BeO on a femtosecond time scale after the passage of highly charged heavy ions. (C) 2013 Elsevier B.V. All rights reserved.

[发布日期] 2013-12-15

[效力级别]  Proceedings Paper

[关键词] Auger-electron emission;Ion-track formation;High electronic excitation density;Short-time electron dynamics;Band-structure variation;Wide-gap insulator;Melting