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arXiv · 2210.13359

Quantum error correction with dissipatively stabilized squeezed cat qubits

Timo Hillmann·Fernando Quijandría
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Abstract

Noise-biased qubits are a promising route toward significantly reducing the hardware overhead associated with quantum error correction. The squeezed cat code, a non-local encoding in phase space based on squeezed coherent states, is an example of a noise-biased (bosonic) qubit with exponential error bias. Here we propose and analyze the error correction performance of a dissipatively stabilized squeezed cat qubit. We find that for moderate squeezing the bit-flip error rate gets significantly reduced in comparison with the ordinary cat qubit while leaving the phase flip rate unchanged. Additionally, we find that the squeezing enables faster and higher-fidelity gates.

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Timo Hillmann, Fernando Quijandría. 2022-10-24. Quantum error correction with dissipatively stabilized squeezed cat qubits. https://doi.org/10.1103/physreva.107.032423

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