Improved handling of piezo stacks with asymmetric voltages

Base package BP5e – Piezo tubes are likely the most common fine positioning method for “standard” SPM measurements. However, a growing number of measurements techniques combining SPM with various sensing methods (magnetometry, TERS,…) also means a more widespread use of piezo-stack based positioners. These positioners are usually operated with asymmetric voltages, in most cases unipolar (positive-only) voltages. Piezo tubes, on the other hand, are almost exclusively operated with voltages being symmetric around 0 V.
One of the advantages of the Nanonis software is that all signals are displayed in calibrated, real-world SI units. The calibration was designed for symmetric voltages, resulting in an unintuitive signal display if the positioner would be operated with asymmetric voltages.
Software V5e release R9226 and V5 release R9170 introduced a number of improvements:

• The Z-controller slider limits reflect the voltage distribution, meaning that a Z=0 position corresponds to a 0 V output on the Z-channel
• The calibration automatically detects if the outputs are set to unipolar and avoid a doubling of the range 
• The output voltage on the X, Y, and Z channels stays at 0 V when starting the controller software irrespective of bipolar or unipolar mode instead of the midrange position for the output (bipolar = 0 V, unipolar = 5 V).

These improvements are available for all V5 and V5e users.