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Steady-state spin synchronization through the collective motion of trapped ions



Athreya Shankar, John Cooper, Justin G. Bohnet, Murray Holland, John Bollinger


Ultranarrow-linewidth atoms coupled to a lossy optical cavity mode synchronize, i.e. develop correlations, and exhibit steady-state superradiance when continuously repumped. This system displays rich collective physics and promises metrological applications. These features inspire us to investigate if analogous spin synchronization is possible in a different platform that is one of the most robust and controllable experimental testbeds currently available: ion-trap systems. We design a system with a primary and secondary species of ions that share a common set of normal modes of vibration. In analogy to the lossy optical mode, we propose to use a lossy normal mode, obtained by sympathetic cooling with the secondary species of ions, to mediate spin synchronization in the primary species of ions. Our numerical study shows that spin-spin correlations develop, leading to a macroscopic collective spin in steady-state. We propose an experimental method based on Ramsey interferometry to detect signatures of this collective spin; we predict that correlations prolong the visibility of Ramsey fringes, and population statistics at the end of the Ramsey sequence can be used to directly infer spin-spin correlations.
Physical Review A


ion trap, normal mode, Penning trap, phonon, spin synchronization, superradiance


Shankar, A. , Cooper, J. , Bohnet, J. , Holland, M. and Bollinger, J. (2017), Steady-state spin synchronization through the collective motion of trapped ions, Physical Review A, [online], (Accessed July 15, 2024)


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Created March 21, 2017, Updated October 12, 2021