Laser Desorption from Metal Oxides
EMSL Project ID
24794
Abstract
This proposal is a continuation of research under EMSL User Proposal #21794. Laser ablation and desorption techniques form the basis of unique methods for producing novel materials, performing sophisticated chemical analysis or medical procedures. Although laser ablation/desorption techniques are utilized extensively across a diverse range of disciplines, detailed mechanistic understanding has proved elusive due to the inherent complexity of the initial laser solid interaction and subsequent particle emission processes. The primary laser absorption may occur through linear or nonlinear mechanisms and through intrinsic or extrinsic photo-centers; further complications are introduced by the many-bodied dynamics that ultimately lead to particle emission. Many of the key processes (i.e. electron-hole recombination, trapping, exciton relaxation, electron/phonon interactions, etc.) occur on a sub-nanosecond time-scale and femtosecond laser studies are needed to clarify the role of ultrafast phenomena involved in laser desorption processes. To obtain detailed understanding of highly complex laser desorption processes, a combined experimental and theoretical effort is essential.
An additional important aspect of this work is determining ultrafast excited electronic state dynamics of wide-band materials. These include processes such as small polaron formation at interfaces between conductors and insulators. To this end we will utilize the XPS interfaced with ultrasfast lasers.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2007-05-29
End Date
2010-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Beck KM, AG Joly, O Diwald, S Stankic, PE Trevisanutto, PV Sushko, AL Shluger, and WP Hess. 2008. "Energy and Site Selectivity in O-Atom Photodesorption from Nanostructured MgO." Surface Science 602(11):1968-1973. doi:10.1016/j.susc.2008.03.046
Beck KM, M Henyk, CM Wang, PE Trevisanutto, P Sushko, WP Hess, and AL Shluger. 2006. "Site-Specific Laser Modification of MgO nanoclusters: Towards Atomic-Scale Surface Structuring." Physical Review. B, Condensed Matter 74:045404 (5 pages).
Joly AG, KM Beck, and WP Hess. 2008. "Electronic Energy Transfer on CaO Surfaces." Journal of Chemical Physics 129(12):124704. doi:10.1063/1.2980049
Joly AG, M Henyk, KM Beck, PE Trevisanutto, PV Sushko, WP Hess, and AL Shluger. 2006. "Probing Electron Transfer Dynamics at MgO Surfaces by Mg-Atom Desorption." Journal of Physical Chemistry B 110(37):18093-18096. doi:10.1021/jp064092b
Trevisanutto PE, PV Sushko, KM Beck, AG Joly, WP Hess, and AL Shluger. 2009. "Excitation, Ionization, and Desorption: How Sub-band-gap Photons Modify the Structure of Oxide Nanoparticles." Journal of Physical Chemistry C 113(4):1274-1279.