attoAFM /CFM
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attoAFM/CFM
combined low temperature atomic force and confocal microscope, tuning fork based
The tuning fork based attoAFM/CFM not only allows fast optical investigation of the sample prior to detailed AFM studies, it also enables
precise positioning of the AFM tip over small structures and optical
control of the scanning process or any surface manipulation. Also,
optical experiments such as Raman spectroscopy and tip enhanced Raman spectroscopy (TERS) can be conducted. Needless to say that all of
these tasks can be performed in extreme environments, such as ultra low
temperature, high vacuum and magnetic fields.
The attoAFM/CFM uses an Akiyama probe tip to investigate tip-sample interaction forces on the nanometer scale. The Akiyama probe is typical-
ly operated in non-contact mode using a phase-locked loop to excite
the probe at resonance and track any shift in frequency due to tip-sample interactions. An additional PI controller keeps the frequency shift
at a constant value while scanning over the
surface. Simultaneously to the information provided by the Akiyama
probe, the CFM reveals complementary optical information of the sample surface. Since the z-scanning motion is provided by a
dedicated scanner on the side of the AFM, the focal distance
between the low-temperature compatible lens and the sample
does not change.
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Principle of atomic-sized magnetic sensors using NV centers.
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01 LT and HV compatible feedthroughs
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02 vacuum window
03 microscope insert
04 superconducting magnet (optional)
05 liquid He dewar (optional)
06 confocal microscope objective
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Schematic drawing of the low
temperature attoAFM/CFM and the
surrounding liquid Helium dewar
(optional)
07 AFM Akiyama probe
08 two xyz coarse positioners and xyz scanner units
09 ultra stable Titanium housing