Optimal Controlled Teleportation

TL;DR

This paper derives conditions and probabilities for optimal controlled teleportation of an unknown qubit using tripartite states, identifying states suitable as perfect quantum channels.

Contribution

It provides analytic expressions for success probabilities, characterizes states enabling perfect controlled teleportation, and introduces a new form of localizable entanglement.

Findings

Maximal success probabilities for controlled teleportation are derived.

Conditions for three-qubit states to serve as perfect quantum channels are established.

A new type of localizable entanglement is identified.

Abstract

We give the analytic expressions of maximal probabilities of successfully controlled teleportating an unknown qubit via every kind of tripartite states. Besides, another kind of localizable entanglement is also determined. Furthermore, we give the sufficient and necessary condition that a three-qubit state can be collapsed to an EPR pair by a measurement on one qubit, and characterize the three-qubit states that can be used as quantum channel for controlled teleporting a qubit of unknown information with unit probability and with unit fidelity.