Heidelberg 2015 – wissenschaftliches Programm
A 40.1: Vortrag
Freitag, 27. März 2015, 11:00–11:15, B/SR
Quadrupole-quadrupole interactions in ultracold atom systems — •Martin Lahrz1, Mikhail Lemeshko2, Klaus Sengstock1, Christoph Becker1, and Ludwig Mathey1 — 1University of Hamburg, Hamburg, Germany — 2Harvard University, Cambridge, Massachusetts, USA
We investigate quadrupole-quadrupole interactions of ultracold atom systems. These interactions have a long-range and anisotropic character, which goes beyond the properties of contact potentials. In this talk, we will report briefly about our proposal  to detect quadrupolar interactions in ultracold Fermi gases by measuring the induced mean-field shift. We consider a quasi-2D system of quadrupoles aligned by an external magnetic field and tilted with respect to the system geometry. This results in a characteristic angular dependence constituting the “smoking gun” feature of this interaction. The magnitude of the shift is of the order of tens of Hertz for Yb(3P2) and similarly for Sr(3P2) making this experimentally conceivable with current technologies. Further, we discuss many-body effects that can be created with quadrupole-quadrupole interactions.
 M. Lahrz, M. Lemeshko, K. Sengstock, C. Becker, and L. Mathey, Phys. Rev. A 89, 043616 (2014).