Teleportation via maximally and non-maximally entangled mixed states

TL;DR

This paper compares the effectiveness of different two-qubit mixed entangled states as resources for quantum teleportation, highlighting conditions where non-maximally entangled states outperform maximally entangled ones.

Contribution

It introduces a new class of non-maximally entangled mixed states and analyzes their teleportation performance relative to existing states like Werner states.

Findings

Werner states yield higher average fidelity than Munro et al.'s states.

Certain non-maximally entangled states outperform Werner derivatives in teleportation.

States can outperform despite not violating Bell-CHSH inequalities.

Abstract

We study the efficacy of two-qubit mixed entangled states as resources for quantum teleportation. We first consider two maximally entangled mixed states, viz., the Werner state\cite{werner}, and a class of states introduced by Munro {\it et al.} \cite{munro}. We show that the Werner state when used as teleportation channel, gives rise to better average teleportation fidelity compared to the latter class of states for any finite value of mixedness. We then introduce a non-maximally entangled mixed state obtained as a convex combination of a two-qubit entangled mixed state and a two-qubit separable mixed state. It is shown that such a teleportation channel can outperform another non-maximally entangled channed, viz., the Werner derivative for a certain range of mixedness. Further, there exists a range of parameter values where the former state satisfies a Bell-CHSH type inequality and still performs better as a teleportation channel compared to the Werner derivative even though the latter violates the inequality.