Measurement of three-dimensional force fields with atomic resolution using dynamic force spectroscopy

Using dynamic force microscopy and spectroscopy in an ultrahigh vacuum (“noncontact atomic force microscopy”) at low temperatures, we measured three-dimensional force fields with atomic resolution. The method is based on the systematic recording of the frequency shift of a cantilever oscillating near the sample surface. The presented experimental results were obtained on a NiO(001) sample surface with an iron-coated silicon tip, but the measurement principle can be extended to any tip–sample system.