The influence of tip-sample interaction on step fluctuations on Ag(111)

SURFACE SCIENCE

卷:400

Article

Mugele, F ; Rettenberger, A ; Boneberg, J ; Leiderer, P

关键词: low index single crystal surfaces;    scanning tunneling microscopy;    silver;    surface diffusion;   

DOI  :  10.1016/S0039-6028(97)00843-1

来源: Elsevier

【 摘 要 】

The fluctuations of the position of monatomic steps on Ag(ll1) are investigated by scanning tunneling microscopy (STM). We analyze the influence of tip-sample interaction by varying the gap impedance over more than two orders of magnitude. For tunneling tips providing a weak tip-sample interaction. wt show that the step position autocorrelation Function remains essentially unaltered. In this unperturbed case, the kinetics of step fluctuations are found to be dominated by one-dimensional mass transport. For larger variations of the rip-sample distance or for less favorable tip configurations. we observe a tip-induced increase of the step fluctuations. Our measurements suggest that this effect is caused rather by short-range Forces than bq the electric field in the tunneling gap. (C) 1998 Elsevier Science B.V.

【 授权许可】

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