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arXiv · 2108.12225

All-optical cat-code quantum error correction

Jacob Hastrup·Ulrik Lund Andersen
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Abstract

The cat code is a promising encoding scheme for bosonic quantum error correction as it allows for correction against losses--the dominant error mechanism in most bosonic systems. However, for losses to be detected efficiently without disturbing the encoded logical information, one needs to implement a parity measurement of the excitation number. While such a measurement has been demonstrated in the microwave regime using a superconducting transmon ancilla, it has remained unclear how it can be implemented in the optical regime. Here, we introduce a teleportation-based error-correction scheme for the cat code, using elements suitable for an optical setting. The scheme detects and corrects single-photon losses while restoring the amplitude of the cat states, thereby greatly suppressing the accumulation of errors in lossy channels.

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Jacob Hastrup, Ulrik Lund Andersen. 2021-08-27. All-optical cat-code quantum error correction. https://arxiv.org/abs/2108.12225

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