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arXiv · 1905.05721

Generation and manipulation of Schr\"odinger cat states in Rydberg atom arrays

Ahmed Omran·Harry Levine·Alexander Keesling·Giulia Semeghini·Tout T. Wang·Sepehr Ebadi·Hannes Bernien·Alexander S. Zibrov·Hannes Pichler·Soonwon Choi·Jian Cui·Marco Rossignolo·Phila Rembold·Simone Montangero·Tommaso Calarco·Manuel Endres·Markus Greiner·Vladan Vuletić·Mikhail D. Lukin
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Abstract

Quantum entanglement involving coherent superpositions of macroscopically distinct states is among the most striking features of quantum theory, but its realization is challenging, since such states are extremely fragile. Using a programmable quantum simulator based on neutral atom arrays with interactions mediated by Rydberg states, we demonstrate the deterministic generation of 'Schr\"odinger cat' states of the Greenberger-Horne-Zeilinger (GHZ) type with up to 20 qubits. Our approach is based on engineering the energy spectrum and using optimal control of the many-body system. We further demonstrate entanglement manipulation by using GHZ states to distribute entanglement to distant sites in the array, establishing important ingredients for quantum information processing and quantum metrology.

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Ahmed Omran, Harry Levine, Alexander Keesling, Giulia Semeghini, Tout T. Wang, Sepehr Ebadi, Hannes Bernien, Alexander S. Zibrov, Hannes Pichler, Soonwon Choi, Jian Cui, Marco Rossignolo, Phila Rembold, Simone Montangero, Tommaso Calarco, Manuel Endres, Markus Greiner, Vladan Vuletić, Mikhail D. Lukin. 2019-05-14. Generation and manipulation of Schr\"odinger cat states in Rydberg atom arrays. https://doi.org/10.1126/science.aax9743

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