Berlin 2005 – wissenschaftliches Programm
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Q: Quantenoptik und Photonik
Q 32: Quantengase I
Q 32.8: Vortrag
Dienstag, 8. März 2005, 12:30–12:45, HU Kinosaal
Optical Feshbach resonances — •Klaus Winkler1, Matthias Theis1, Gregor Thalhammer1, Rudolf Grimm1,2, and Johannes Hecker Denschlag1 — 1Institut für Experimentalphysik, Universität Innsbruck, Austria — 2Institut für Quantenoptik und Quanteninformation, Innsbruck, Austria
We demonstrated optical tuning of the scattering length in a Bose-Einstein condensate as predicted by Fedichev et al. [1]. In our experiment atoms in a 87Rubidium condensate were exposed to laser light tuned close to the transition frequency to a molecular state. The optical coupling of the atomic scattering state to the molecular state gives rise to what is called an optical Feshbach resonance. We showed that the optical Feshbach resonance can be induced via one or two photon transitions. While for the one photon transition we coupled to an excited molecular state [2], we used a stimulated Raman scheme for the two photon case to couple to the molecular ground state [3]. By controlling the power and the detuning of the lasers we were able to change the atomic scattering length over a wide range. We identified Bragg spectroscopy as a fast method (<100µs) to measure the scattering length of the atoms in view of rapid laser-driven atomic losses.
[1] P.Fedichev et al., Phys.Rev.Lett. 77, 2913 (1996)
[2] M. Theis et al., Phys.Rev.Lett. 93, 123001 (2004)
[3] G. Thalhammer et al., cond-mat 0409552 (2004)