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DOE OSTI · 1852939

Spin-momentum entanglement in a Bose–Einstein condensate

Kale, Sumit Suresh·Ding, Yijue·Chen, Yong P.·Friedrich, Bretislav·Kais, Sabre
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Abstract

Here, entanglement is at the core of quantum information processing and may prove essential for quantum speed-up. Inspired by both theoretical and experimental studies of spin-momentum coupling in systems of ultra-cold atoms, we investigate the entanglement between the spin and momentum degrees of freedom of an optically trapped BEC of 87 Rb atoms. We consider entanglement that arises due to the coupling of these degrees of freedom induced by Raman and radio-frequency fields and examine its dependence on the coupling parameters by evaluating von Neumann entropy as well as concurrence as measures of the entanglement attained. Our calculations reveal that under proper experimental conditions significant spin-momentum entanglement can be obtained, with von Neumann entropy of 80% of the maximum attainable value. Our analysis sheds some light on the prospects of using BECs for quantum information applications.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Kale, Sumit Suresh, Ding, Yijue, Chen, Yong P., Friedrich, Bretislav, Kais, Sabre. 2020-10-27. Spin-momentum entanglement in a Bose–Einstein condensate. https://doi.org/10.1039/d0cp03945d

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