Figure 2
Imaging and spectroscopy on HOPG at a covered step edge in AMFlex2-OLTor1-FMLat1 mode with 863 pm lateral-eigenmode-amplitude setpoint. (a–e) Schemes of the tip trajectory for the coupled second flexural and first torsional cantilever oscillation for decreasing second flexural-eigenmode-amplitude setpoints Aflex,2. The setpoints of Aflex,2 are listed in the first, the corresponding setpoints of the first-torsional-eigenmode amplitude Ator,1 in the second row and the approximate z-sensor position at the third row. The values in brackets represent the percentages of the setpoints from the free amplitudes A0(flex,2) and A0(tor,1). (f) Second flexural-, (l) first torsional-eigenmode amplitude Ator,1 and (r) first lateral frequency shift Δflat,1 vs. z-sensor position, where the crossed circles mark the positions at which the images where taken. (g–k) Height, (m–q) first torsional-eigenmode amplitude error ΔAtor,1 and (s–w) Δflat,1 images at decreasing Aflex,2. Note, that Φtor,1 was assumed to be 90° for the calculation of the tip-trajectories shown in (a–e).
