First-principles time-dependent simulation of laser assisted desorption of hydrogen atoms from H-Si(111) surface

The dynamics of hydrogen desorption from H-terminated silicon surface clusters has been simulated in the framework of real space time-dependent density functional theory complemented with molecular dynamics for ions. It has been demonstrated that by choosing an appropriate frequency and intensity of the laser it is possible to remove the hydrogen layer from the surface without destroying the structure of underlying silicon. At the laser field intensities used in the current study (0.5-2.0 V/Å) the desorption process is notably nonlinear.