Orateur
Sadhan Adhikari
(São Paulo State University, Institute of Theoretical Physics)
Description
Trapped degenerate dipolar Bose and Fermi gases of cylindrical symmetry
with the polarization vector along the symmetry axis are only stable for the strength
of dipolar interaction below a critical value. In the case of bosons, the stability of
such a dipolar Bose-Einstein condensate (BEC) is investigated for different strengths
of contact and dipolar interactions using variational approximation and numerical
solution of a mean-field model. In the disk shape, with the polarization vector
perpendicular to the plane of the disk, the atoms experience an overall dipolar repulsion
and this fact should contribute to the stability. However, a complete numerical solution
of the dynamics leads to the collapse of a strongly disk-shaped dipolar BEC as well as a Fermi superfluid. A collapse can be induced in
a disk-shaped stable binary Bose-Fermi mixture by jumping the interspecies contact interaction from repulsive
to attractive by the Feshbach resonance technique. Collapse and fragmentation in the fermions after subsequent
explosions are illustrated. The present study is carried out in three-dimensional space using
realistic values of dipolar and contact interactions.
Auteur principal
Sadhan Adhikari
(São Paulo State University, Institute of Theoretical Physics)
