Demonstrating an element of measurement-based quantum error correction

TL;DR

This paper demonstrates quantum error detection in measurement-based quantum computing using a four-qubit photonic cluster state, addressing noise effects crucial for realistic quantum computing implementations.

Contribution

It introduces a protocol for quantum error detection in measurement-based quantum computing under noisy conditions, using a photonic cluster state.

Findings

Successful detection of phase errors in a four-qubit photonic cluster state

First demonstration of error detection in measurement-based quantum computing with noise

Analysis of output states after decoding confirms error detection capability

Abstract

In measurement-based quantum computing an algorithm is performed by measurements on highly-entangled resource states. To date, several implementations were demonstrated, all of them assuming perfect noise-free environments. Here we consider measurement-based information processing in the presence of noise and demonstrate quantum error detection. We implement the protocol using a four-qubit photonic cluster state, where we first encode a general qubit non-locally such that phase errors can be detected. We then read out the error syndrome and analyze the output states after decoding. Our demonstration shows a building block for measurement-based quantum computing which is crucial for realistic scenarios.