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arXiv · 1501.03862

Entangling Atomic Spins with a Strong Rydberg-Dressed Interaction

Y. -Y. Jau·A. M. Hankin·Tyler Keating·I. H. Deutsch·G. W. Biedermann
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Abstract

Controlling quantum entanglement between parts of a many-body system is the key to unlocking the power of quantum information processing for applications such as quantum computation, high-precision sensing, and simulation of many-body physics. Spin degrees of freedom of ultracold neutral atoms in their ground electronic state provide a natural platform given their long coherence times and our ability to control them with magneto-optical fields, but creating strong coherent coupling between spins has been challenging. We demonstrate a Rydberg-dressed ground-state blockade that provides a strong tunable interaction energy ($\sim$1 MHz in units of Planck's constant) between spins of individually trapped cesium atoms. With this interaction we directly produce Bell-state entanglement between two atoms with a fidelity $\geq$ 81(2)%, excluding atom loss events, and $\geq$ 60(3)% when loss is included.

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Y. -Y. Jau, A. M. Hankin, Tyler Keating, I. H. Deutsch, G. W. Biedermann. 2016-01-05. Entangling Atomic Spins with a Strong Rydberg-Dressed Interaction. https://doi.org/10.1038/nphys3487

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