Electric trapping of slow polar molecules
Max-Planck Institut f. Quantenoptik, Garching
in the field of cold molecules depends on the ability to
make beams of slow molecules, and to cool and trap these. We have
demonstrated a novel method to create a slow molecular beam from
an effusive source of polar molecules (ND3, H2CO or D2O).
Molecules from a room-temperature effusive source are injected
into a bent electrostatic quadrupole guide, which acts as a
velocity filter for molecules in low-field-seeking Stark states.
These molecules are transported into another chamber, where they
can be handled in an ultrahigh vacuum. Here, we have successfully
built a large volume electrostatic trap that is filled
continuously from the guide. Molecules with velocities smaller
than about 20 m/s are trapped with a motional temperature of about
0.3 K. The findings should find applications in cold chemistry, which is,
apart from its fundamental interest, for instance of interest for astrophysics.