Detecting quadrupole interactions in ultracold Fermi gases

4 February 2014

Photo: Copyright by the American Physical Society Lahrz et al., PRA 89, 4, 043616 (2014)

We propose to detect quadrupole interactions of neutral ultra-cold atoms via their induced mean-field shift. We consider a Mott insulator state of spin-polarized atoms in a two-dimensional optical square lattice. The quadrupole moments of the atoms are aligned by an external magnetic field. As the alignment angle is varied, the mean-field shift shows a characteristic angular dependence, which constitutes the defining signature of the quadrupole interaction. For the 3P2 states of Yb and Sr atoms, we find a frequency shift of the order of tens of Hertz, which can be realistically detected in experiment with current technology. We compare our results to the mean-field shift of a spin-polarized quasi-2D Fermi gas in continuum.

Read the original article: Lahrz et al.,  Phys. Rev. A, 89, 4, 043616 (2014)