Erlangen 2018 – wissenschaftliches Programm
Q 52.5: Vortrag
Donnerstag, 8. März 2018, 11:30–11:45, K 0.011
Precision measurement of the dynamical polarizability of dysprosium at 1064nm — Cornelis Ravensbergen1,2, •Vincent Corre1,2, Elisa Soave2, Marian Kreyer1,2, Slava Tzanova1,2, Emil Kirilov2, and Rudolf Grimm1,2 — 1Institut für Quanten Optik und Quanten Information, Innsbruck — 2Institut für Experimental Physik, Universität Innsbruck
The field of ultracold dipolar gases has grown vastly in the last years, motivated by the new phases made accessible by the long-range anisotropic dipole-dipole interaction. Among dipolar systems, atomic gases of lanthanides - erbium and dysprosium - have been cooled down to the degenerate regime and have demonstrated striking dipolar effects. But while the geometry of the trapping potential is known to have a critical influence on the behavior of these gases, questions remain about the value of the dynamical polarizability of dysprosium, as a large discrepancy still exists between theoretical calculations and experimental measurements. We report on a new measurement of the dynamical polarizability of dysprosium at 1064 nm with unprecedented precision. We take advantage of our dual-species experimental set-up and use potassium as a reference species. By calibrating the polarizability of dysprosium on the one of potassium, which is well known, we free ourselves from the main sources of systematic error that are the trapping laser waist and aberrations, and anharmonicity effects. We check that other possible error sources have negligible effect. Eventually we obtain values for the scalar and tensor parts of the polarizability with a relative error of 2%, that are close to the theoretical predictions.