The relation between the quantum discord and quantum teleportation: the physical interpretation of the transition point between different quantum discord decay regimes

TL;DR

This paper investigates how the decay regimes of quantum discord influence the efficiency of quantum teleportation using Bell-diagonal states, revealing a physical interpretation of the transition point between different discord decay behaviors.

Contribution

It establishes a direct link between the transition in quantum discord decay regimes and changes in teleportation fidelity, providing a physical understanding of discord dynamics.

Findings

Transition point coincides with change in teleportation fidelity behavior

Different state parameters affect teleportation difficulty

Quantum discord decay regimes relate to teleportation efficiency

Abstract

We study quantum teleportation via Bell-diagonal mixed states of two qubits in the context of the intrinsic properties of the quantum discord. We show that when the quantum-correlated state of the two qubits is used for quantum teleportation the character of the teleportation efficiency changes substantially depending on the Bell-diagonal-state parameters, which can be seen when the worst-case-scenario or best-case-scenario fidelity is studied. Depending on the parameter range, one of two types of single qubit states is hardest/easiest to teleport. The transition between these two parameter ranges coincides exactly with the transition between the range of classical correlation decay and quantum correlation decay characteristic for the evolution of the quantum discord. The correspondence provides a physical interpretation for the prominent feature of the decay of the quantum discord.