[제원호교수/이만희학생] Phys. Rev. Lett. 에 논문 게재
We present a general analytical theory that enables one to determine accurately the unknown tip-sample interactions from the experimental measurement of the amplitude and phase of the oscillating tip in amplitude-modulation atomic force microscopy (AM-AFM). We apply the method to the known Lennard-Jones-type forces and find excellent agreement with the reconstructed results. AM-AFM, widely used in air and liquid, is now not only an atomic-resolution imaging tool but also a quantitative force measurement tool.