Abstract
We present control of force sensitivity in Q -controlled amplitude-modulation atomic force microscopy (AM-AFM) that is based on the high- Q quartz tuning-fork. It is found that the phase noise is identical to the amplitude noise divided by oscillation amplitude in AM-AFM. In particular, we observe that while Q -control does not compromise the signal-to-noise ratio, it enhances the detection sensitivity because the minimum detectable force gradient is inversely proportional to the effective quality factor for large bandwidths, which is due to reduction of frequency noise. This work demonstrates Q -control in AM-AFM is a useful technique for enhancement of the force sensitivity with increased Q or improvement of the scanning speed with decreased Q .
Original language | American English |
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Article number | 054302 |
Journal | Physics Faculty Publications and Presentations |
Volume | 114 |
Issue number | 5 |
DOIs | |
State | Published - 7 Aug 2013 |
Keywords
- Q-factor
- atomic force microscopy
- phase noise
- quartz
- vibrations
EGS Disciplines
- Physics