Microscopy
Controllers
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PLL
A fully digital phase-locked loop is implemented into the ASC500. It uses the
high frequency inputs / outputs with 50 MHz bandwidth. A high-speed Lock-In
demodulator and two PI control loops are used to control the amplitude of an
oscillator and to follow any resonance shifts. The frequency resolution is below
0.2 µHz in a range of 1 kHz up to 2 MHz. Therefore, it is possible to
• gain access to direct measurement of force gradients by means of measuring
• ∆f have a clear PLL concept with graphical interface and access to all data
• streams in the PLL chain
Measurement Modes
STM: constant height (with tilt correction), constant current
AFM: contact mode, amplitude modulation, frequency modulation (PLL),
Kelvin Probe, Scanning Gate Microscopy (SGM), Piezo Response Force
Microscopy (PRFM) MFM: constant height (with tilt correction), dual pass
mode, CFM: constant height, step scan mode for increased scan ranges.
Data Processing
Collection of data is the most important task in every experiment. The
ASC500 was built to give the user every possibility to view, process, and
save all data streams. Data can be visualized in 1D, 2D, or 3D displays. Furthermore, the ASC500 features are:
• real-time FFT calculation and background filtering
• full control over all raw and processed data
• global snapshot functionality: a user definable collection of data can be
• saved with only one mouse click
• saving of parameters in a text file
attoCONTROL
Electronic & Software Control Units