An All Optical Fibre Quantum Controlled-NOT Gate

TL;DR

This paper demonstrates the first all-optical fibre quantum CNOT gate, achieving high fidelity, and identifies photon source imperfections as the main limitation, advancing fibre-based quantum computing technology.

Contribution

It presents the first experimental realization of a fibre-based quantum CNOT gate with high fidelity, highlighting the potential for integrated quantum photonic circuits.

Findings

Average logical fidelity of 90%

Process fidelity between 0.83 and 0.91

Imperfections mainly due to photon sources

Abstract

We report the first experimental demonstration of an optical controlled-NOT gate constructed entirely in fibre. We operate the gate using two heralded optical fibre single photon sources and find an average logical fidelity of 90% and an average process fidelity of 0.83<F<0.91. On the basis of a simple model we are able to conclude that imperfections are primarily due to the photon sources, meaning that the gate itself works with very high fidelity.