Multiport based teleportation -- transmission of a large amount of quantum information

TL;DR

This paper investigates port-based quantum teleportation, deriving bounds on performance that enable teleportation of larger quantum information amounts, with explicit formulas for fidelity and success probability, especially in the qubit case.

Contribution

It introduces a computable lower bound on teleportation fidelity that surpasses previous explicit bounds, enabling more efficient transmission of quantum information.

Findings

Derived a lower bound on entanglement fidelity for port-based teleportation.

Provided closed-form formulas for fidelity and success probability in the qubit case.

Demonstrated improved performance bounds over existing protocols.

Abstract

We analyse the problem of transmitting a number of unknown quantum states or one composite system in one go. We derive a lower bound on the performance of such process, measured in the entanglement fidelity. The obtained bound is effectively computable and outperforms the explicit values of the entanglement fidelity calculated for the pre-existing variants of the port-based protocols, allowing for teleportation of a much larger amount of quantum information. The comparison with the exact formulas and similar analysis for the probabilistic scheme is also discussed. In particular, we present the closed-form expressions for the entanglement fidelity and for the probability of success in the probabilistic scheme in the qubit case in the picture of the spin angular momentum.