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arXiv · 2004.11790

Spin-exchange collisions in hot vapors create and sustain bipartite entanglement

K. Mouloudakis·I. K. Kominis
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Abstract

Spin-exchange collisions in alkali or alkali/noble gas vapors are at the basis of quantum sensing, nucleon structure studies, tests of fundamental symmetries, and medical imaging. We here show that spin-exchange collisions in hot alkali vapors naturally produce strong bipartite entanglement, which we explicitly quantify using the tools of quantum information science. This entanglement is shown to have a lifetime at least as long as the spin-exchange relaxation time, and to directly affect measurable spin noise observables. This is a formal theoretical demonstration that a hot and dense atomic vapor can support longlived bipartite and possibly higher-order entanglement.

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K. Mouloudakis, I. K. Kominis. 2020-04-24. Spin-exchange collisions in hot vapors create and sustain bipartite entanglement. https://doi.org/10.1103/physreva.103.l010401

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