Gwyscope documentation

Goal of the quantitative mechanics measurement regime is to evaluate local mechanical properties using off-resonance tapping (ORT) technique for feedback and evaluating the individual force-distance curves obtained during this process.

To make it work, a periodic excitation in the range of hundreds of nanometers has to be added to the cantilever motion, which allows the probe to snap in contact, measure a force-distance dependence in the contact, determine the maximum value of force for feedback loop, leave the contact providing an adhesion value and then to repeate this process again and again. To make it work we need to use an additional shaker piezo or to combine internally the signal generator 1 (from lock-in 1) with 20-bit z-piezo signal and shake with the whole z-piezo.

To use this mode with Gwyscope GUI, first adjust the probe signal like you would do it in contact mode. Then switch to “QM” regime (while still being out of contact). Use “Adjust sensor” button to call the QM settings dialogue, which should look like this:

Set the parameters for the measurement regime - for the beginning it is enough to set the frequency and amplitude and to set the fit range to cover entire signal.