arXiv:1308.5209 · Physical Review A

Demonstrating elements of measurement-based quantum error correction

Stefanie Barz, Rui Vasconcelos, Chiara Greganti, Michael J. Zwerger, Wolfgang Dür, Hans J. Briegel, Philip John Walther

Published Oct 2, 2014• 15 citations

Abstract

In measurement-based quantum computing an algorithm is performed by measurements on highly entangled resource states. To date, several implementations were demonstrated, most 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 nonlocally 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.

DOI: 10.1103/physreva.90.042302

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