The automation of robust interatomic-force measurements

TL;DR

This paper develops algorithms and software to automate the inflection point test, improving the reliability of interatomic-force measurements in atomic force microscopy.

Contribution

It advances the theoretical framework and creates user-friendly software for automated, robust force data validation in atomic force microscopy.

Findings

Automated algorithms successfully implement the inflection point test.

Software enables seamless, reliable force measurements in experimental datasets.

The approach improves robustness and reliability of nanoscale force measurements.

Abstract

Interatomic-force measurements are regularly performed using frequency-modulation atomic force microscopy. This requires conversion of the observed shift in the resonant frequency of a force-sensing cantilever, to the actual force experienced by its tip. Recently, Sader et al. Nature Nanotechnology 13, 1088 (2018) showed that this force conversion can be unreliable and proposed the inflection point test to identify valid and robust force data. Efficient and user-friendly algorithms are required for its routine practical implementation, which currently do not exist. Here, we (1) advance the theoretical framework of the inflection point test, (2) develop the required efficient algorithms for its complete automation, and (3) demonstrate the utility of this automation by studying two experimental datasets. The principal outcome of this report is the development of user-friendly software that integrates this automation with a standard force conversion methodology. This software provides the enabling technology for practitioners to now seamlessly perform robust nanoscale and interatomic-force measurements.