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arXiv · 2302.07526

Macroscopic maximally entangled state preparation between two atomic ensembles

Manish Chaudhary·Ebubechukwu O. Ilo-Okeke·Valentin Ivannikov·Tim Byrnes
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Abstract

We develop a scheme to prepare a macroscopic maximally entangled state (MMES) between two atomic ensembles using adaptive quantum nondemolition (QND) measurements. The quantum state of the system is evolved using a sequence of QND measurements followed by adaptive unitaries, such that the desired measurement outcome is obtained with asymptotically unit probability. This procedure is repeated in z and x spin basis alternately such that the state converges deterministically towards the maximally entangled state. Up to a local spin-basis rotation, the maximally entangled state has zero total spin angular momentum, i.e. it is a singlet state. Our protocol does not perform postselection and works beyond the Holstein-Primakoff regime for the atomic spin degrees of freedom, producing genuine macroscopic entanglement.

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Manish Chaudhary, Ebubechukwu O. Ilo-Okeke, Valentin Ivannikov, Tim Byrnes. 2023-02-15. Macroscopic maximally entangled state preparation between two atomic ensembles. https://arxiv.org/abs/2302.07526

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