Rydberg excitation of cesium atoms in vapor cells at room temperature
Rydberg atoms in dense gases are of growing interest, due to the rich many-body physics enabled by the strong interactions. In particular, the effect of Rydberg aggregation, which relies on off-resonant excitation to spatially correlated ensembles of atoms, is currently studied [1,2] as it exhibits interesting correlations, as e.g. in soft-matter systems .
We present our experimental results on the excitation dynamics of such Rydberg aggregates in a vapor cell at room temperature . The scaling laws for the characteristic timescale of the excitation process are consistent with a model based on an effective Master equation. Moreover, we show that our measurements are very sensitive to the interaction potentials. We are able to observe the influence dipole-quadrupole interactions.
We will also examine the definition of aggregates when thermal motion is non-negligible and the influence of having predominantly motional dephasing rather than laser dephasing.
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