  Piezoelectric quartz tuning forks are investigated in view of their use as
force sensors in dynamic mode scanning probe microscopy at temperatures down to
1.5 K and in magnetic fields up to 8 T. The mechanical properties of the forks
are extracted from the frequency dependent admittance and simultaneous
interferometric measurements. The performance of the forks in a cryogenic
environment is investigated. Force-distance studies performed with these
sensors at low temperatures are presented.
