Automatic Generation of Contrast Maps in Terms of van der Waals Material Properties in Bimodal AFM

Abstract

van der Waals (vdW) forces are of interest in colloid science, biophysics, cell biology, and the field of vdW heterostructures. We present a model and method to quantify vdW material properties of samples routinely in standard bimodal atomic force microscopy (AFM) without the need to establish mechanical contact with the samples. The method preserves the high resolution of bimodal AFM but enhances contrast by exploiting several transforms that lead to the production of contrast maps in the form of vdW material properties, i.e., Hamaker constant, adhesion, surface energy, peak forces, and surface energy hysteresis. We show that some of these maps provide information that is otherwise concealed in the raw channels.