Laser control of product electronic state: desorption from alkali halides.
We demonstrate laser control of the electronic product state distribution of photodesorbed halogen atoms from alkali halide crystals. Our general model of surface exciton desorption dynamics is developed into a simple method for laser control of the relative halogen atom spin-orbit laser desorption yield. By tuning the excitation laser photon energy in a narrow region of the absorption threshold, the yield of excited state chorine atoms, Cl(2P(1/2)), can be made to vary from near 0 to 80% for KCl and from near 0 to 50% for NaCl relative to the total yield of Cl atoms. We describe the physical properties necessary to obtain a high degree of product state control and the limitation induced when these requirements are not met. These results demonstrate that laser control can be applied to solid state surface reactions and provide strong support for surface exciton-based desorption models.
Beck
Kenneth M
KM
Pacific Northwest National Laboratory, William R. Wiley Environmental Molecular Sciences Laboratory, Richland, Washington 99352, USA. kenneth.beck@pnl.gov
Joly
Alan G
AG
Dupuis
Nicholas F
NF
Perozzo
Peggy
P
Hess
Wayne P
WP
Sushko
Peter V
PV
Shluger
Alexander L
AL