Tip-sample interactions on graphite studied using the wavelet transform

• Giovanna Malegori and
• Gabriele Ferrini

Beilstein J. Nanotechnol. 2010, 1, 172–181, doi:10.3762/bjnano.1.21

• , i.e., signal with a frequency spectrum changing during the data collection. This work will show that the tip-sample interaction forces can be quantitatively measured using CWT with acquisition times as short as few tens of milliseconds, as required for practical DFS imaging. Since wavelets are a

• of the PSD as a function of z. Considering each flexural mode equivalent to a mass-spring system, the tip-sample interaction elastic constant kts = −dFts/dz is expressed as a function of the resonant frequency as , where is the resonant frequency of the free cantilever, is the resonant frequency of

• effect of the tip-sample interaction dominates. Continuous wavelet transform and time-frequency resolution The FT analysis provides a frequency representation of a signal with perfect spectral resolution but without the possibility to correlate the frequency spectrum with the signal evolution in time

Sensing surface PEGylation with microcantilevers

• Natalija Backmann,
• Natascha Kappeler,
• Thomas Braun,
• François Huber,
• Hans-Peter Lang,
• Christoph Gerber and
• Roderick Y. H. Lim

Beilstein J. Nanotechnol. 2010, 1, 3–13, doi:10.3762/bjnano.1.2

• on the AFM images can be understood by comparing the tip-sample interaction forces obtained in PBS and 20% 2-propanol, respectively (Figure 5). Specifically, the thickness of the PEG layer (defined by the onset of repulsion) reduces from 26 nm in the brush-like state to 5 nm in the collapsed state