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Bound states in multilayers of cold polar molecules

### Jeremy R. Armstrong

**Wednesday, 8 June 2011, 14:00**

Matfys library

**Abstract**:

The experimental realization of cold polar molecules in the rotational and
vibrational ground state opens the door to the study of a wealth of
phenomena involving long-range interactions. By applying an optical
lattice to a gas of cold polar molecules one can create a layered system
of planar traps. Due to the long-range dipole-dipole interaction one
expects a
rich structure of bound complexes in this geometry. We study the bilayer
case and determine the two-body bound-state properties as a function of
the interaction strength. The results clearly show that a least one bound
state will always be present in the system. In addition, bound states at
zero energy show universal behavior and extend to very large radii. These
results suggest that non-trivial bound complexes of more than two
particles are likely in the bilayer and in more complicated chain
structures in multilayer systems. We use a harmonic approximation to
study the behavior of the chain structures.