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Exploring Noiseless Subsystems via Nuclear Magnetic Resonance

Evan M. Fortunato·Lorenza Viola·Marco A. Pravia·Emanuel Knill·Raymond Laflamme·Timothy F. Havel·David G. Cory
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Abstract

Noiseless subsystems offer a general and efficient method for protecting quantum information in the presence of noise that has symmetry properties. A paradigmatic class of error models displaying non-trivial symmetries emerges under collective noise behavior, which implies a permutationally-invariant interaction between the system and the environment. We describe experiments demonstrating the preservation of a bit of quantum information encoded in a three qubit noiseless subsystem for general collective noise. A complete set of input states is used to determine the super-operator for the implemented one-qubit process and to confirm that the fidelity of entanglement is improved for a large, non-commutative set of engineered errors. To date, this is the largest set of error operators that has been successfully corrected for by any quantum code.

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Evan M. Fortunato, Lorenza Viola, Marco A. Pravia, Emanuel Knill, Raymond Laflamme, Timothy F. Havel, David G. Cory. 2002-10-09. Exploring Noiseless Subsystems via Nuclear Magnetic Resonance. https://doi.org/10.1103/physreva.67.062303

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