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Register a new userAn efficient, concatenated, bosonic code for additive Gaussian noise
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Bosonic codes offer noise resilience for quantum information processing. A common type of noise in this setting is additive Gaussian noise, and a long-standing open problem is to design a concatenated code that achieves the hashing bound for this noise channel. Here we achieve this goal using a Gottesman-Kitaev-Preskill (GKP) code to detect and discard error-prone qubits, concatenated with a quantum parity code to handle the residual errors. Our method employs a linear-time decoder and has applications in a wide range of quantum computation and communication scenarios.
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