Speaker
Description
Quantum error correction (QEC) is essential for protecting quantum information from ubiquitous environmental noises. The Gottesman-Kitaev-Preskill (GKP) state is a particularly promising bosonic QEC code state that can protect the information encoded in an oscillator against dominant bosonic errors. Approximate GKP states can be generated by performing adaptive phase estimation with an ancilla qubit, yet existing proposals usually require a high-quality qubit to attain good GKP states. Here, we propose a method to generate GKP states with a dephasing qubit ancilla. We find that dephasing error would alter and reduce the inferred knowledge about phase, but these effects can simply be compensated by more rounds of phase estimation. We introduce a modified phase estimation process that optimizes the inferred phase knowledge with ancilla dephasing fully considered. Our simulation demonstrate that high-fidelity GKP states can still be generated even when the ancilla dephasing is significant. Our results improve the practicality of bosonic QEC in realistic platforms.
| Keyword-1 | Quantum error correction |
|---|---|
| Keyword-2 | Adaptive phase estimation |
| Keyword-3 | Ancilla errors |