Remote restoring of $(0,1)$-excitation states and concurrence scaling

TL;DR

This paper investigates the process of remotely restoring (0,1)-excitation states in a quantum chain governed by the XX-Hamiltonian, revealing how coherence and entanglement scale during transfer.

Contribution

It demonstrates that restoring the 1-excitation coherence matrix also restores the 1-excitation block of the 0-order matrix, with a Hamiltonian-dependent concurrence scaling.

Findings

Restoring 1-excitation coherence restores most of the 0-excitation matrix.

Concurrence between qubits scales with a factor determined by the Hamiltonian.

Sender-Receiver entanglement analyzed via PPT criterion.

Abstract

We study the long distance (0,1)-excitation state restoring in the linear open chain governed by the XX-Hamiltonian. We show that restoring the 1-order coherence matrix results in restoring the 1-excitation block of the 0-order coherence matrix, so that only one 0-excitation element of the density matrix remain unrestored. Such restoring also scales the concurrence between any two qubits of the transferred state, the scaling factor is defined by the Hamiltonian and doesn't depend on the initial sender's state. Sender-Receiver entanglement is also studied via the PPT criterion.