# Asymptotic Performance of Port-Based Teleportation

@article{Christandl2021AsymptoticPO, title={Asymptotic Performance of Port-Based Teleportation}, author={Matthias Christandl and Felix Leditzky and Christian Majenz and Graeme Smith and Florian Speelman and Michael Walter}, journal={Communications in Mathematical Physics}, year={2021}, volume={381}, pages={379 - 451} }

Quantum teleportation is one of the fundamental building blocks of quantum Shannon theory. While ordinary teleportation is simple and efficient, port-based teleportation (PBT) enables applications such as universal programmable quantum processors, instantaneous non-local quantum computation and attacks on position-based quantum cryptography. In this work, we determine the fundamental limit on the performance of PBT: for arbitrary fixed input dimension and a large number N of ports, the error of…

## 16 Citations

Multiport based teleportation -- protocol and its performance

- Computer Science
- 2020

A lower bound on the performance of the protocol, measured in the entanglement fidelity, is derived using equivalence between the teleportation process and state discrimination task and it is obtained that maximal number of faithfully teleported systems differs qualitatively in deterministic and probabilistic scheme.

Optimality of the pretty good measurement for port-based teleportation

- Computer Science
- 2020

This paper gives an explicit proof that the so-called pretty good measurement, or square-root measurement, is optimal for the PBT protocol with independent copies of maximally entangled states as the port state, and shows that the very same measurement remains optimal even when theport state is optimized to yield the best possible P BT protocol.

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

- Computer Science, PhysicsQuantum
- 2021

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.

Square-root measurements and degradation of the resource state in port-based teleportation scheme

- Computer Science
- 2021

This paper analyzes for the first time the recycling protocol for the deterministic PBT beyond the qubit case and presents the explicit formula for the recycling fidelity involving only group-theoretic parameters describing irreducible representations in the Schur-Weyl duality.

Minimal Port-based Teleportation

- Computer Science
- 2021

The minimal set of requirements that define a feasible P BT protocol are introduced and a simple PBT protocol is constructed that satisfies these requirements: it teleports an unknown state of a qubit with success probability psucc = 1− N+2 2N+1 and fidelity 1−O( 1 N ) with the resource state consisting of N maximally entangled states.

Optimization and learning of quantum programs

- Computer Science
- 2019

This work proves that the search for the optimal quantum program is a convex optimization problem, and applies this general result to a number of different designs for the programmable quantum processor, from the shallow protocol of quantum teleportation, to deeper schemes relying on port-based teleportation and parametric quantum circuits.

Infinite-Dimensional Programmable Quantum Processors

- Computer SciencePRX Quantum
- 2021

This work generalizes the concept of a finite-dimensional programmable quantum processor to infinite dimension assuming an energy constraint on the input and output of the target quantum channels and gives upper and lower bounds on the program dimension of a processor implementing all Gaussian unitary channels.

Algebraic and Statistical ways into Quantum Resource Theories

- Physics
- 2019

Quantum information science is one of the most active, intellectually stimulating, and technologically promising areas in science. It offers a unique opportunity to engage in a wide variety of…

Approximate Programmable Quantum Processors in Infinite Dimensions

- Computer Science, Physics
- 2020

This work generalizes the concept of a finite-dimensional programmable quantum processor to infinite dimensions assuming an energy constraint on the input and output of the target quantum channels.

Efficient multi port-based teleportation schemes

- Physics
- 2020

Michał Studziński1, Marek Mozrzymas2, Piotr Kopszak2 and Michał Horodecki3 1 Institute of Theoretical Physics and Astrophysics and National Quantum Information Centre in Gdańsk, Faculty of…

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