Demonstration of fault-tolerant universal quantum gate operations

By L. Postler, Sascha Heußen, I. Pogorelov, M. Rispler, T. Feldker, Michael Meth, Christian D. Marciniak, R. Stricker, Martin Ringbauer, Rainer Blatt and 3 more. Nature, 2021

333 citations recorded by the source corpus.

Quantum computers can be protected from noise by encoding the logical quantum information redundantly into multiple qubits using error-correcting codes1,2. When manipulating the logical quantum states, it is imperative that errors caused by imperfect operations do not spread uncontrollably through the quantum register. This requires that all operations on the quantum register obey a fault-tolerant circuit design3–5, which, in general, increases the complexity of the implementation. Here we demonstrate a fault-tolerant universal set of gates on two logical qubits in a trapped-ion quantum computer. In particular, we make use of the recently introduced paradigm of flag fault tolerance, where the absence or presence of dangerous errors is heralded by the use of auxiliary flag qubits6–10. We perform a logical two-qubit controlled-NOT gate between two instances of the seven-qubit colour code11,12, and fault-tolerantly prepare a logical magic state8,13. We then realize a fault-tolerant logical T gate by injecting the magic state by teleportation from one logical qubit onto the other14. We observe the hallmark feature of fault tolerance—a superior performance compared with a non-fault-tolerant implementation. In combination with recently demonstrated repeated quantum error-correction cycles15,16, these results provide a route towards error-corrected universal quantum computation. A fault-tolerant, universal set of single- and two-qubit quantum gates is demonstrated between two instances of the seven-qubit colour code in a trapped-ion quantum computer.

Subfields: Artificial Intelligence, Computational Theory and Mathematics

View Paper: https://www.semanticscholar.org/paper/0a46767e18434894120a9df2bd5d6955e62c6a03

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Artificial Intelligence

In Computational Theory and Mathematics

Citations in the corpus

Quantum error mitigation (2022, background): “Meanwhile other experiments have indeed demonstrated early-stage fault-tolerant potentials [see e.g. Abobeih et al. (2022); Egan et al. (2021); Google Quantum AI (2023); Krinner et al. (2022); Postler et al. (2022); Ryan-Anderson et al. (2022); and Takeda et al. (2022)].”