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arXiv · 2108.08372

Enhancing entanglement and total correlations dynamics via local unitaries

Joab Morais Varela·Ranieri Nery·George Moreno·Alice Caroline de Oliveira Viana·Gabriel Landi·Rafael Chaves
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Abstract

The interaction with the environment is one of the main obstacles to be circumvented in practical implementations of quantum information tasks. The use of local unitaries, while not changing the initial entanglement present in a given state, can enormously change its dynamics through a noisy channel, and consequently its ability to be used as a resource. This way, local unitaries provide an easy and accessible way to enhance quantum correlations in a variety of different experimental platforms. Given an initial entangled state and a certain noisy channel, what are the local unitaries providing the most robust dynamics? In this paper we solve this question considering two qubits states, together with paradigmatic and relevant noisy channels, showing its consequences for teleportation protocols and identifying cases where the most robust states are not necessarily the ones imprinting the least information about themselves into the environment. We also derive a general law relating the interplay between the total correlations in the system and environment with their mutual information built up over the noisy dynamics. Finally, we employ the IBM Quantum Experience to provide a proof-of-principle experimental implementation of our results.

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Joab Morais Varela, Ranieri Nery, George Moreno, Alice Caroline de Oliveira Viana, Gabriel Landi, Rafael Chaves. 2021-08-18. Enhancing entanglement and total correlations dynamics via local unitaries. https://arxiv.org/abs/2108.08372

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