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arXiv · 0811.4185

Investigation of dephasing rates in an interacting Rydberg gas

U. Raitzsch·R. Heidemann·H. Weimer·V. Bendkowsky·B. Butscher·P. Kollmann·R. Löw·H. P. Büchler·T. Pfau
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Abstract

We experimentally and theoretically investigate the dephasing rates of the coherent evolution of a resonantly driven pseudo spin emersed in a reservoir of pseudo spins. The pseudo spin is realized by optically exciting 87 Rb atoms to a Rydberg state. Hence, the upper spin states are coupled via the strong van der Waals interaction. Two different experimental techniques to measure the dephasing rates are shown: the 'rotary echo' technique known from nuclear magnetic resonance physics and electromagnetically induced transparency. The experiments are performed in a dense frozen Rydberg gas, either confined in a magnetic trap or in an optical dipole trap. Additionally, a numerical simulation is used to analyse the dephasing in the rotary echo experiments.

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U. Raitzsch, R. Heidemann, H. Weimer, V. Bendkowsky, B. Butscher, P. Kollmann, R. Löw, H. P. Büchler, T. Pfau. 2008-11-25. Investigation of dephasing rates in an interacting Rydberg gas. https://doi.org/10.1088/1367-2630%2F11%2F5%2F055014

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