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arXiv · 1704.08982

Cavity Carving of Atomic Bell States

Stephan Welte·Bastian Hacker·Severin Daiss·Stephan Ritter·Gerhard Rempe
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Abstract

We demonstrate entanglement generation of two neutral atoms trapped inside an optical cavity. Entanglement is created from initially separable two-atom states through carving with weak photon pulses reflected from the cavity. A polarization rotation of the photons heralds the entanglement. We show the successful implementation of two different protocols and the generation of all four Bell states with a maximum fidelity of (90+-2)%. The protocol works for any distance between cavity-coupled atoms, and no individual addressing is required. Our result constitutes an important step towards applications in quantum networks, e.g. for entanglement swapping in a quantum repeater.

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Stephan Welte, Bastian Hacker, Severin Daiss, Stephan Ritter, Gerhard Rempe. 2017-04-28. Cavity Carving of Atomic Bell States. https://doi.org/10.1103/physrevlett.118.210503

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