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arXiv · 2006.06092

Loss-of-entanglement prediction of a controlled-PHASE gate in the framework of steepest-entropy-ascent quantum thermodynamics

J. A. Montañez-Barrera·Cesar E. Damian-Ascencio·Michael R. von Spakovsky·Sergio Cano-Andrade
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Abstract

As has been shown elsewhere, a reasonable model of the loss of entanglement or correlation that occurs in quantum computations is one which assumes that they can effectively be predicted by a framework that presupposes the presence of irreversibilities internal to the system. It is based on the steepest-entropy-ascent principle and is used here to reproduce the behavior of a controlled-PHASE gate in good agreement with experimental data. The results show that the loss of entanglement predicted is related to the irreversibilities in a nontrivial way, providing a possible alternative approach that warrants exploration to that conventionally used to predict the loss of entanglement. The results provide a means for understanding this loss in quantum protocols from a nonequilibrium thermodynamic standpoint. This framework permits the development of strategies for extending either the maximum fidelity of the computation or the entanglement time.

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J. A. Montañez-Barrera, Cesar E. Damian-Ascencio, Michael R. von Spakovsky, Sergio Cano-Andrade. 2020-06-10. Loss-of-entanglement prediction of a controlled-PHASE gate in the framework of steepest-entropy-ascent quantum thermodynamics. https://doi.org/10.1103/physreva.101.052336

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