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arXiv · 1711.06971

Resonance enhancement of two photon absorption by magnetically trapped atoms in strong rf-fields

A. Chakraborty·S. R. Mishra
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Abstract

Applying a many mode Floquet formalism for magnetically trapped atoms interacting with a polychromatic rf-field, we predict a large two photon transition probability in the atomic system of cold $^{87}Rb$ atoms. The physical origin of this enormous increase in the two photon transition probability is due to the formation of avoided crossings between eigen-energy levels originating from different Floquet sub-manifolds and redistribution of population in the resonant intermediate levels to give rise to the resonance enhancement effect. Other exquisite features of the studied atom-field composite system include the splitting of the generated avoided crossings at the strong field strength limit and a periodic variation of the single and two photon transition probabilities with the mode separation frequency of the polychromatic rf-field. This work can find applications to characterize properties of cold atom clouds in the magnetic traps using rf-spectroscopy techniques.

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A. Chakraborty, S. R. Mishra. 2017-11-19. Resonance enhancement of two photon absorption by magnetically trapped atoms in strong rf-fields. https://doi.org/10.1016/j.physleta.2017.11.016

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