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arXiv · 1901.02557

Engineering excited-state interactions at ultracold temperatures

Michael Mills·Prateek Puri·Ming Li·Steven J. Schowalter·Alexander Dunning·Christian Schneider·Svetlana Kotochigova·Eric R. Hudson
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Abstract

Using a recently developed method for precisely controlling collision energy, we observe a dramatic suppression of inelastic collisions between an atom and ion (Ca + Yb$^+$) at low collision energy. This suppression, which is expected to be a universal phenomenon, arises when the spontaneous emission lifetime of the excited state is comparable to or shorter than the collision complex lifetime. We develop a technique to remove this suppression and engineer excited-state interactions. By dressing the system with a strong catalyst laser, a significant fraction of the collision complexes can be excited at a specified internuclear separation. This technique allows excited-state collisions to be studied, even at ultracold temperature, and provides a general method for engineering ultracold excited-state interactions.

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Michael Mills, Prateek Puri, Ming Li, Steven J. Schowalter, Alexander Dunning, Christian Schneider, Svetlana Kotochigova, Eric R. Hudson. 2019-01-08. Engineering excited-state interactions at ultracold temperatures. https://doi.org/10.1103/physrevlett.122.233401

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