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Entanglement Echoes in Quantum Computation

Davide Rossini·Giuliano Benenti·Giulio Casati
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Abstract

We study the stability of entanglement in a quantum computer implementing an efficient quantum algorithm, which simulates a quantum chaotic dynamics. For this purpose, we perform a forward-backward evolution of an initial state in which two qubits are in a maximally entangled Bell state. If the dynamics is reversed after an evolution time $t_r$, there is an echo of the entanglement between these two qubits at time $t_e=2t_r$. Perturbations attenuate the pairwise entanglement echo and generate entanglement between these two qubits and the other qubits of the quantum computer.

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Davide Rossini, Giuliano Benenti, Giulio Casati. 2003-09-19. Entanglement Echoes in Quantum Computation. https://doi.org/10.1103/physreva.69.052317

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