Loading...

Atomic interactions between metallic tips and surfaces in NC-AFM

Pishkenari, H. N ; Sharif University of Technology | 2015

1046 Viewed
  1. Type of Document: Article
  2. DOI: 10.1088/0022-3727/48/12/125301
  3. Publisher: Institute of Physics Publishing , 2015
  4. Abstract:
  5. In this paper, the atomic-scale interactions between metallic tips and samples in noncontact atomic force microscopy (NC-AFM) are studied using molecular dynamics simulations. The effects of the tip and sample materials, the surface plane direction and the lateral position of the tip with respect to the sample, on the interaction force and the dissipated energy, are investigated. The simulations conducted demonstrate that, generally, we can classify the possible outcomes for the dynamics due to the tip-surface interactions into four major categories. The first category includes all cases in which there are no considerable instabilities in tip-surface interactions, leading to negligible energy loss (dissipated energy < 3 meV/cycle), while the other three categories consist of cases with reversible or irreversible reconstruction of the tip and the surface. For the second category, there is a hysteresis loop in the interaction force and in the displacement of the system atoms depending significantly on the surface plane direction, the surface density, the cohesive energy of the tip and the surface, the adhesive energy between tip apex atom and the surface, and the adhesive energy between a surface atom and the tip. The third and fourth categories include cases with irreversible changes in the tip or the surface. Based on the adhesive and cohesive energies of the tip and the surface, we have proposed a simple and rapid criterion capable of predicting the category to which each setup belongs
  6. Keywords:
  7. Cohesive and adhesive energies ; NC-AFM ; Tip-surface interaction forces ; Atomic force microscopy ; Molecular dynamics ; Adhesive energy ; AFM ; Atomic interactions ; Atomic-scale interaction ; Irreversible changes ; Molecular dynamics simulations ; Noncontact atomic force microscopy ; Tip-surface interaction ; Energy dissipation
  8. Source: Journal of Physics D: Applied Physics ; Volume 48, Issue 12 , February , 2015 ; 00223727 (ISSN)
  9. URL: http://iopscience.iop.org/article/10.1088/0022-3727/48/12/125301/meta