Computer simulations of hyperchanneling of low energy ions in semichannelsof Pt(111)-(1 x 1) surface

Lui, KM Fang, ZL Lau, WM Rabalais, JW

Km. Lui et al., Computer simulations of hyperchanneling of low energy ions in semichannelsof Pt(111)-(1 x 1) surface, NUCL INST B, 182, 2001, pp. 200-206

15

INGLESE

Article

Spectroscopy /Instrumentation/Analytical Sciences","Instrumentation & Measurement

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

0168-583X → ACNP

182

2001

200 - 206

ISI

0168-583X(200108)182:<200:CSOHOL>2.0.ZU;2-T

The scattering and recoiling imaging code (SARIC) was employed to perform c lassical ion trajectory simulations of hyperchanneling phenomenon of low en ergy noble gas ions on the Pt(111)-(1x1) surface. It was found that under p roper conditions, incident ions can indeed possess oscillatory trajectories within one single open semichannel in the first atomic layer of the Pt sur face, which confirmed the concept of hyperchanneling. This special scatteri ng phenomenon was explained by the fact that the smooth overlapping of atom ic potentials of the atoms lining the walls of the semichannel effectively provides a potential trap along the trajectories of the incident ions resul ting in the hyperchanneling. In addition, it was found that the mass of the ions had a profound effect on the conditions to achieve hyperchanneling. D etailed simulations revealed that hyperchanneled ions suffered very little energy loss and energy spread upon exiting the surface. Due to the ultrahig h sensitivity of hyperchanneling ions to minute corrugations of the potenti als of the atomic walls, hyperchanneling can be utilized to determine the s urface Debye temperature, which is one of the important parameters to model most surface reactions. (C) 2001 Elsevier Science B.V. All rights reserved .