Restoring genuine tripartite entanglement under local amplitude damping

TL;DR

This paper explores methods to restore genuine tripartite entanglement affected by local amplitude damping, demonstrating that pre- and post-decoherence reversal schemes can effectively retrieve entanglement.

Contribution

It introduces a scheme using CNOT and Hadamard gates for entanglement restoration, highlighting the importance of applying reversal operations before and after decoherence.

Findings

Entanglement retrieval is more effective with pre- and post-decoherence reversal.

Mixtures of W and GHZ states show improved entanglement recovery.

No enhancement in entanglement lifetime when recovery is applied after decoherence.

Abstract

We investigate the possibility to restore genuine tripartite entanglement under local amplitude damping. We show that it is possible to protect genuine entanglement using CNOT and Hadamard gates. We analyze several ordering of such recovery operations. We find that for recovery operations applied after exposing qubits to decoherence, there is no enhancement in lifetime of genuine entanglement. Actual retrieval of entanglement is only possible when reversal scheme is applied before and after the decoherence process. We find that retrieval of entanglement for mixture of $|\widetilde{W}\rangle$ state with white noise is more evident than the respective mixture of $|W\rangle$ state. We also find the retrieval of entanglement for similar mixture of $|GHZ\rangle$ state as well.