RETRACTED: Desorption of H from Si(111) by resonant excitation of the Si-H vibrational stretch mode.
Past efforts to achieve selective bond scission by vibrational excitation have been thwarted by energy thermalization. Here we report resonant photodesorption of hydrogen from a Si(111) surface using tunable infrared radiation. The wavelength dependence of the desorption yield peaks at 0.26 electron volt: the energy of the Si-H vibrational stretch mode. The desorption yield is quadratic in the infrared intensity. A strong H/D isotope effect rules out thermal desorption mechanisms, and electronic effects are not applicable in this low-energy regime. A molecular mechanism accounting for the desorption event remains elusive.
Liu
Zhiheng
Z
Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Feldman
L C
LC
Tolk
N H
NH
Zhang
Zhenyu
Z
Cohen
P I
PI