The absolute values of the force exerted by the fiber probe of a scanning near-field optical microscope onto the surface were measured using an atomic force microscope in ambient conditions. We demonstrate that a usually neglected static attraction force is dominant at small dither amplitudes and is of the order of 200 nN. The tapping component of the force, often referred to as shear force, is of the order of 1 nN at these conditions for both the tuning fork-based and optical in resonance detection schemes. Other peculiarities of the shear force interaction are also discussed.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)