Quantum teleportation and entanglement swapping with linear optics logic gates

TL;DR

This paper demonstrates the use of linear optics phase gates to distinguish Bell states in quantum teleportation and entanglement swapping, achieving high fidelity and confirming non-classical correlations through Bell inequality violations.

Contribution

It introduces a linear optics phase gate that can distinguish all Bell states simultaneously, improving quantum teleportation and entanglement swapping protocols.

Findings

Average state fidelity of 0.83 and 0.77 for teleportation and swapping

Successful violation of Bell inequality with a value of 2.14

Full state and process tomography confirming non-classical properties

Abstract

We report on the usage of a linear optics phase gate for distinguishing all four Bell states simultaneously in a quantum teleportation and entanglement swapping protocol. This is demonstrated by full state tomography of the one and two qubit output states of the two protocols, yielding average state fidelities of about 0.83 and 0.77, respectively. In addition, the performance of the teleportation channel is characterised by quantum process tomography. The non classical properties of the entanglement swapping output states are further confirmed by the violation of a CHSH-type Bell inequality of 2.14 on average.