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arXiv · 1603.01810

Dynamics of a ground-state cooled ion colliding with ultra-cold atoms

Ziv Meir·Tomas Sikorsky·Ruti Ben-shlomi·Nitzan Akerman·Yehonatan Dallal·Roee Ozeri
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Abstract

Ultra-cold atom-ion mixtures are gaining increasing interest due to their potential applications in quantum chemistry, quantum computing and many-body physics. Here, we studied the dynamics of a single ground-state cooled ion during few, to many, Langevin (spiraling) collisions with ultra-cold atoms. We measured the ion's energy distribution and observed a clear deviation from Maxwell-Boltzmann to a Tsallis characterized by a power-law tail of high energies. Unlike previous experiments, the energy scale of atom-ion interactions is not determined by either the atomic cloud temperature or the ion's trap residual excess-micromotion energy. Instead, it is determined by the force the atom exerts on the ion during a collision which is then amplified by the trap dynamics. This effect is intrinsic to ion Paul traps and sets the lower bound of atom-ion steady-state interaction energy in these systems. Despite the fact that our system is eventually driven out of the ultra-cold regime, we are capable of studying quantum effects by limiting the interaction to the first collision.

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Ziv Meir, Tomas Sikorsky, Ruti Ben-shlomi, Nitzan Akerman, Yehonatan Dallal, Roee Ozeri. 2016-07-10. Dynamics of a ground-state cooled ion colliding with ultra-cold atoms. https://doi.org/10.1103/physrevlett.117.243401

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