Tuning the dipolar interaction in quantum gases

Phys Rev Lett. 2002 Sep 23;89(13):130401. doi: 10.1103/PhysRevLett.89.130401. Epub 2002 Sep 4.


We have studied the tunability of the interaction between permanent dipoles in Bose-Einstein condensates. Based on time-dependent control of the anisotropy of the dipolar interaction, we show that even the very weak magnetic dipole coupling in alkali gases can be used to excite collective modes. Furthermore, we discuss how the effective dipolar coupling in a Bose-Einstein condensate can be tuned from positive to negative values and even switched off completely by fast rotation of the orientation of the dipoles.