Generation and manipulation of Schrödinger cat states in Rydberg atom arrays
arXiv:1905.05721 · doi:10.1126/science.aax9743
The paper demonstrates deterministic creation of multi‑qubit Greenberger‑Horne‑Zeilinger (GHZ) Schrödinger cat states using a programmable array of neutral atoms with Rydberg interactions, and shows how to manipulate and distribute this entanglement across the array.
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 'Schrödinger 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.
6 pages, 4 figures + Supplementary Materials (8 pages, 9 figures, 1 table)