Atomic-scale nanoindentation: detection and identification of single glide events in threedimensions by force microscopy

Abstract

Indentation experiments on the nanometre scale have been performed by means of atomicforce microscopy in ultra-high vacuum on KBr(100) surfaces. The surfaces yield in the formof discrete surface displacements with a typical length scale of 1 Å. These surfacedisplacements are detected in both normal and lateral directions. Measurement of thelateral tip displacement requires a load-dependent calibration due to the load dependenceof the effective lateral compliance. Correlation of the lateral and normal displacementsfor each glide event allow identification of the activated slip system. The resultsare discussed in terms of the resolved shear stress in indentation experimentsand of typical results in atomistic simulations of nanometre-scale indentation.