Interactions of Rydberg atoms in a Bose-Einstein condensate

吕昊, 朱少兵, Jun Qian +1 more

Jia Wang, Marko Gacesa, Robin Côté

We investigate a hybrid system composed of ultracold Rydberg atoms immersed in an atomic Bose-Einstein condensate (BEC). The coupling between Rydberg electrons and BEC atoms leads to excitations of phonons, the exchange of which induces a Yukawa interaction between Rydberg atoms. Because of the small electron mass, the effective charge associated with this quasiparticle-mediated interaction can be large. Its range, equal to the BEC healing length, is tunable using Feshbach resonances to adjust the scattering length between BEC atoms. We find that for small healing lengths, the distortion of the BEC can "image" the Rydberg electron wave function, while for large healing lengths the induced attractive Yukawa potentials between Rydberg atoms are strong enough to bind them.

Kashif Ammar Yasir, Wu-Ming Liu

Georg A. Raithel

Avra Banerjee, Dwipesh Majumder

Abstract In this work, we investigated a Bose-Einstein condensate (BEC) inside a Rydberg atom. We first observed the system’s density profile using the Gross-Pitaevskii equation, and then we used the Bogoliubov theory to examine the collective excitation spectra. We have also extended our study by taking into account a hybrid of two BEC species. Again, for this new system, the density profile and the collective excitation are investigated in a similar manner. The results of the BEC for one species reveal that the Rydberg atom can trap the BEC and that the excitation curve moves upward with increasing Rydberg atom interaction. We have seen roton minima for two species of BEC, and the depth of the minima shifts with the Rydberg interaction.

Matthias Weidemüller, M. Reetz‐Lamour, Thomas Amthor +3 more