Single-State ELectronic Structure Measurements Using Time-Resolved X-Ray Laser Induced Photoelectron Spectroscopy.

Nelson, A. J. ; Dunn, J. ; van Buuren, T. ; Hunter, J.

Technical Information Center Oak Ridge Tennessee

关键词: Photoelctron spectroscopy;    Electronic structure;    Metal surfaces;    Semiconductors;    Spectroscopy;   

RP-ID  :  DE200515014573

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

We demonstrate single-shot x-ray laser induced time-of-flight photoelectron spectroscopy on semiconductor and metal surfaces with picosecond time resolution. The LLNL COMET compact tabletop x-ray laser source provides the necessary high photon flux (>1012/pulse), monochromaticity, picosecond pulse duration, and coherence for probing ultrafast changes in the chemical and electronic structure of these materials. Static valence band and shallow core-level photoemission spectra are presented for ambient temperature Ge(100) and polycrystalline Cu foils. Surface contamination was removed by UV ozone cleaning prior to analysis. In addition, the ultrafast nature of this technique lends itself to true single-state measurements of shocked and heated materials. Time-resolved electron time-of-flight photoemission results for ultra-thin Cu will be presented.