Error Rates and Resource Overheads of Repetition Cat Qubits

Understand

We estimate and analyze the error rates and the resource overheads of the repetition cat qubit approach to universal and fault-tolerant quantum computation.

• The cat qubits stabilized by two-photon dissipation exhibit an extremely biased noise where the bit-flip error rate is exponentially suppressed with the mean number of photons.
• In a recent work, we suggested that the remaining phase-flip error channel could be suppressed using a 1D repetition code.
• Indeed, using only bias-preserving gates on the cat-qubits, it is possible to build a universal set of fault-tolerant logical gates at the level of the repetition cat qubit.